Thursday, September 19, 2019

8th Edition Warhammer 40,000 Exposes Poor Generals.

There are very few places in 8th Edition for a poor General to hide.

In the past, a very good list could stop the most infantile of Generals from being exposed.  Not so good at the game?  Play the Eldar Scatter spam in 7E or while it lasted the Ynnari in 8E.  Castellan+ Ig was similar for a bit, but only for a bit.  While your highs wont be much higher than other peoples (as we discussed in a previous blog) your lows won't be NEARLY as low playing as those kinds of things.  You'll look more competent at the game in general, even if you wont win more tournaments.

In 8th Edition, the rule set is slimmed down substantially and the things that made certain units flat broken (Formations) are gone.  It's just you, your unit and a world filled with almost no cover saves and a whole lot of re-rolls.

The balance of power has swung sharply to favor the better generals in this environment.  MANY more lists are viable than were ever before.  I love that.  The unit you use is mattering so much less than how you use it and when.  Let's set the table with two examples.

Consider the innocuous Razorwing Flock.  The Razorwing Flock is about as useless as a second head.  It says 8 attacks, but they hit on 5's and are at a minuscule STR that guarantees they will need 6's to wound almost anything they try to hit.  In other words, you can count on them to do exactly nothing.  So what's the point really?

Another example:  the Kroot Carnivore.  Once this represented the only melee unit you had and with three attacks on the charge it was at least competent, if not stellar, at its job.  As editions went by it became less and less excellent at its job until finally, it is now just getting one attack (admittedly at STR 4 now), and nothing else to distinguish it in any way.  It's 6+ save is essentially trumped most of the time and T3 is pedestrian.  It is really just a fragile boltgun.  Yet it has proven to have extreme value in 8th edition, moreso than it enjoyed in all of 7th Edition even when they could take sniper rounds (which was also taken from them in 8th).

These two examples are good ones to focus on because they illustrate the point I'm making pretty well.  I would not play without Kroot despite all their disabilities.  I've had Kroot Hounds in my list all of 8th Edition as well because they play roles well.

In the case of the Razorwing, it actually does two things for a general.  The First is that it allows you to saturate the enemy line with the promise of being unable to attack for quite a while.  You can make the unit quite large and they literally just move towards the enemy to "blind" them.  So in a very real way, the unit can be thought of more as a blinding screen than an actual unit.  Its multiple wounds make it exceptionally hard to stop it from happening.  A huge swath of the enemy can be charged, have no damage inflicted whatsoever on them (sadly) and then have all of them forced to fall back, robbing the enemy, for a very economical cost, of an entire shooting phase.  Moreover, it is like a drinking game.  Once you start losing a drinking game, it goes downhill fast as the compounding effects of losing means you have progressively less defense against its effects, for in the subsequent round, those same birds are just going to do it again, and this time only face your overwatch.  The frustration of this happening is considerable.  More annoying is when they consolidate in and lock up yet more units.  A very large unit of these is inexpensive and incredibly dangerous to an enemy's chances.  Morale will whittle the birds down but the BeastMaster bolsters that a fair amount and ensures that the death of a thousand papercuts will continue apace.

Yet on its own, the unit is so terrible that no one who looks at it and a comparable 120 points is going to think "wow, that's a great kill ratio".

The Kroot are similarly deceptive in what they provide.  In the new age of 8th Edition Warhammer 40,000, the concept of what I coined as a Halo is important.  Many weapons are most deadly at shorter ranges and many forces now feature a scatter-free parachute assault type of mechanic where they come in flawlessly 9" from their target.  It's kind of a big deal now in 8th Edition.

The Kroot Carnivore Squad does one thing that's great:  It gets a 7" scout move before the first turn starts, which allows you to form a halo outward.  So if the unit you're defending is at point A, an enemy cannot come within 9".  If the Kroot move to point B, which is 18" from Point A, you have formed a pre-game 18" no mans land between the Kroot Carnivores and their charges, and 9" more from the Kroot to where the enemy must now drop.  Collective'ly a 27" no fly Zone thanks to their Vanguard move.  That's pretty impressive because a LOT of weapons don't even shoot more than 24".  With a Kroot Shaper around to help, a larger Kroot unit can stand sentinel and protect a very large portion of the board from drop spam like the Militarum Tempestus, Night Lords or Blood Angels.

Fire Warriors and Pathfinders are far more effective killers and survivors than the Kroot .  But the ability to stall the enemy offensive in this way is pretty impressive.  Kroot Hounds which are now a separate unit make for a useful way to plug the inevitable holes in the halo, so you can hold that halo for a couple of turns at least before ultimately having to give the enemy their chance at you. 

Good Generals are having a really good time in 8th Edition.  They can rely on roles so much more than before.  Their enemies will need to become more creative in their approach than just spamming "the best thing in the codex" seven times.  List variety has definitely improved in 8E, as people discover the little guys, what they can do for a force and how to interlock them in a jigsaw puzzle of success. Ask Plaguebearers. Ask Orks which are finally Krumpin' again.

There will always be the players who only ever play the most powerful thing there is, but it's quite comforting to know that it won't save them.  Skill matters more.

Wednesday, September 18, 2019

The State of The Sisters of Battle

I did a review of the codex recently and thought I'd share it with you!

Celestine:  essentially an auto-include.  Say what you will about the fact that she gives up the King Slayer secondary points so easily in ITC matches.  My answer to that is:  so what, she does her job.  She takes pressure off your army when you need it, and puts pressure on the enemy as long as she's alive and that's a real thing of value in this game, in my opinion.  Currently I don't think her two guardians are worth taking, but that's a call you can make.  For my money, she's better off alone without the Geminae.

Canoness:  She will want to EITHER carry the Brazier relic OR the Sword, depending on the foe.  Because you may change the relic from game to game (but must list the first relic on your list) choose another character as the "normal" relic carrier and leave this one fluid to change.  I would also say that she is your basic force multiplier, as most Imperial armies have to buff your shooting and assaults, so she sort of just goes into the category of "why wouldn't you take at least one".  Every force you face will have some similar utility in it in competitive play, that's fo' sho'.  The Index version of the Eviscerator is better, so if you don't take a Power Sword, look that up and take it.

Missionary/Uriah:  As you will quickly find, Arco-Flagellents are simply an auto-include and that means so is a Missionary.  One can easily argue whether Uriah is necessary, but I think he is definitely worth just a few extra points.  Either way you'll need one.  Advance him every chance you get to keep up and assist in the charges.

Sisters of Battle:  Most of the lists you see with Sisters of Battle are min/maxed weapons caddies.  This is twice as true if you use the Forge World (booooo) Repressors because you can stuff two 5-lady Sisters into it with a total of 6 Meltas!  I mean a Repressor chassis that can run around firing 6 meltaguns out of its ports is kinda potent.  Add to this that you can get a 4+ invulnerable save on them by having Indomitable Belief Warlord Trait coupled with Celestines aura.

 Even if you're not doing this, most people will tell you that because the Sisters aren't individually super expensive (point wise), taking small units with heavy load outs maximizes the heavy weapons on the table very affordably.  I don't agree with this being better, but it sounds great when you read it, doesn't it?  The really real reality is that small units just start losing the heavy weaponry that much faster in small units ,and give up Butchers Bill as a secondary far too easily (and you're already giving up King Slayer easily with Celestine!).  Further, the Acts of Faith can be a significant play if you learn to maximizetheir usefulness and small units or armoeed ones limit your number of Faith Points.  It also limits the VALUE of those Faith Points.  All in all I would rather consider the extra models in the larger units of Sisterrs AS your rhino, if that makes sense.  Advancing gets you nearly as far as a rhino will and with +3" moves, your first unit (generally your screen in many cases) may well move 15" total.  I'm just saying:  consider it.

Arco-Flagellents:  There simply is no better unit in your army to handle ork rushes.  As my Battle Reports show you pretty clearly, they were super stars in all games against hordes.  They also served ADMIRABLY as Engineers for the Secondary Objective of the same name.  They are remarkably versatile.  Breathe hard enough on them and they die, but on the offensive, they are peerless in the Codex.  Keep a Missionary near them at all times and then use your 2 Point stratagem to maximize their number of attacks.  The result is pretty breathe taking.  I use just six in my force and they are never coming out of my list.  They don't occupy an Elites slot, so be aware that if you're trying to fill a certain number of elite slots, they don't do so.

Sisters Repentia:  Here is a unit that is SLIGHTLY underrated.  They don't cost as many CP to run effectively, compared to the Arco-Flagellents.  They are really meant to strike at a different type of target, such as armored things, Damons with annoying Feel No Pain against which multiple wound weapons can pay dividends and so on.  Their primary benefit over the Arco-Flagellents is that it will benefit from the Shield fo Faith and therefore, they are FAR tougher to wound in the first place than the Arco-Flagellents who only have "Feel No Pain".  But this is highly dependent on Celestine staying close.  Given lets say 20 bolter shots. 4.44 unsaved wounds on the Repentia beats 5.9 unsaved wounds on Arco-Flagellents but the difference is the Arco-Flagellents will only lose 3 total of their number while Repentias lose closer to 4.  All in all this is a marginal difference.  Arco-Flagellents have so many attacks that the Sisters Repentia really need a points reduction if they are going to be relevant but they do an admirable job against armor and larger enemies.  They benefit a ton from having a Mistress of Repentance.  Only multi-wound damage weapons being fired at them truly make the Repentias look better for the elites slot, but that is an unlikely scenario more often than it isn't, because most such weapons won't be aimed at them anyways.

Hospitaller:  A great addition to a force, especially if you lack a lot of Faith Points, or didn't afford Celestians (and Emperor knows you better not have).  Its an elite slot filler which is handy for all kinds of list building reasons.  Her attacks don't suck and she can be made your Warlord if you need one.  No matter the Warlord you choose you'll want the Book of St. Lucius on her most likely and in this case it serves two purposes:  one to add to Indomitable Belief Warlord Trait and second, to increase her heal aura so she can better afford to advance every turn and still be within range of more people to heal as needed.  Assassins are now a thing.  A Hospitaller can be a great weapon against them.  Add to this the actual Act of Faith that heals wounds, and you can quickly see how she might be useful, inexpensive, a great slot filler and not a terri-bad combatant with her Tools (as such comparisons go within our codex).

Imagifier (Index):  I don't want to forget this.  She's not in the Codex but is important.  The Imagifier is a character that carries a Simulacrum Imperialis, allowing the model to be +1 on its own Acts of Faith.  The trick here is to have one of these and then to use it to get the +1 to shooting buff.  Seems silly, until you realize that what you're really doing is giving the Imagifier the buff so that it can then share it with all the units within 6" using the Vessel of the Emperor Stratagem!  The +1 makes it far more likely to go off.  Now I personally selected the Ebon Chalice as my <Order>, and so the Imagifier is actually +2 to get Acts of Faith off, and re-rolling with a Dialogus near.  Another use for this is the "Fights Twice" Act of Faith.  Normally it only goes off on a 5+.  But if the Imagifier does it, it's a 3+ and again with a Dialogus I am re-rolling!  So if you have a Canoness with the Sword of Admonition and Celestine and a bunch of sisters around, that is a LOT of extra attacks.  If the Missionary is close enough (he often isn't) this means all those involved are getting his +1 attack twice!  The Imagifier isn't inexpensive and that may turn someone off.  Don''t let it.  Acts of Faith are our defining special rule and making no use of it makes no sense!  If you don't have a lot of Command Points, you may find the Imagifier less useful since Vessel of the Emperors Will is a whopping 3CP to use.  But in my list, I am benefiting from it heavily and the Imagifier makes sense.

Dialogus:  Also an Elite and a great bargain.  You need this in your force since they let you re-roll your critical Acts of Faith.  Acts of Faith are the defining thing about our army and so you would be much remiss not to insure they go off every chance you can get them off.  They make leadership easier to pass as well and when a Missionary is around, the buffs to leadership significantly protect you from some of the new Psyker shenanigans like Purge Soul, Mind War and so on from casualty losses.  When you take larger units of Sisters, you will see larger casualty counts within them but not to worry!  The Dialogus is there to buff you with the missionary.  You'd have to lose 5 Sisters to even be in jeopardy of losing one to morale.  Add to this the Rally the Faithful Stratagem and you may never have to SPEND the 2 CP to auto rally a unit aaaaand...  If you have THREE units that need to rally, you can use Insane heroism stratagem for one, Rally the Faithful for another and then an Act of Faith to save another.  That's three units you potentially can save from desertion in one round without being forced to take the <Order> that mitigates leadership losses.  Pretty impactful in the ITC which scores progressively on Killing more than your enemy.  Denying enemies those points is key.  The Dialogus helps you do it.  That buff is easy to forget.  Don't.

Crusaders:  These guys fill a niche that really no other unit does for Sister of Battle.  I consider them a very simple tool with one mission:  never let the VIP be th closest to the enemy.  By carrying Storm Shields around, it takes forever for enemies to tear through these units, which are there pretty much like a shield wall to protect some character you cant afford to lose.  They can kind of fight also, but that is sort of secondary to their true value.  3 attacks with a Missionary each is really good and they are zealots which matters.  They will never output the kind of offence of the Arco-Flagellents but will FAR outlast them on any objective.  An especially exposed objective is a really good place to put these hard to kill little guys.  It's a niche unit for sure but it has the virtue of being able to get across the field to where you need them without fear for their frailty.  Being a speed bump of significant toughness, or LIne Breaking and other duties like it are all good reasons to consider them.

Death Cult Assassin:  Accompanied by a Ministorum Preiest as usual, they are 5 attacks death blenders, re-rolling misses.  That's damn good.  At STR 3 its a little bit less impressive than Repentia Sisters or Arco-Flagellents can be, but they are definitely capable of a lot of destruction.  Unlike the other two, there really is no CP cost to maximize their value, which makes them a different proposition than just whether it can do more work or not.  It can do ENOUGH and they draw attention.  If I didn't take Arco-Flagellents, I'd use these instead.

Celestians Squads:  Waste of time.  It has been for several codex's running.  They're 2 attack sisters of battle who can carry some gear,  but mostly just die when characters nearby get sniped They are just extra wounds to whomever needs them.  There are other ways to erase wounds in the army.  I'm not spending a single point on this unit.  If I'm doing my job correctly, my characters, other than Celestine, will be the least of their worries and St. Celestine isn't going to be hanging around some slow moving Celestians anyways.  It's not THAT easy to snipe characters dead in one go.  Let your Acts of Faith and so on work for you.

Seraphim: true work horses.  Small squads are plenty, most of the time.  I mostly recommend you have three units of them, with the Fusion pistols. They've done absolute work for me and are fast enough to get away with just being "weapons caddys", counter to my advice otherwise which I gave in the Sisters of Battle section.  I have killed more Dreadnoughts, Assassins and characters with them than I can count.  They are a great surgical unit, fantastic looking models and they just get the job done.  Sisters of Battle can be played as a fast army (though nowhere near as fast as in the Index), but ESPECIALLY in my version, the need for some additional threat saturation early is important and they deliver.

Dominion:  These were absolutely incredible in previous iterations, but in the newest Chapter Approved Codex, I'm really not sold any longer.  The trouble with them is multi-fold.  They seduce you with their scout move which is just absolutely fantastic and immediately makes you want to commit to three of them because you can be seriously threatening very quickly.  The thing that has dampened them is that Repressors with normal sisters (as aforementioned) can bring more meltaguns to the party than the Dominions can, and the Sisters of Battle have Strength of Faith (what we used to call "Objective Secured") which Dominion do not.  With a 4+ invulnerable save potential, many Repressor players are just willing to dare the enemy to try and kill those Repressors instead of relying on the scout move.  Scoring objectives easier and getting 6 Meltas instead of 5 just makes sense if you're using min/maxed units (IF).  The other thing that hurt Dominions is that they essentially must go forward without the support from characters to maximize their chances, while walking into the enemies meltaguns if they don't go first or risk losing the advantages of their deployment shenanigans (and then why are they there at all?).  You can see the risk/Reward problem there.  Getting wrapped around by hordes would be an equally bad outcome if they do move forward while not going first.  Dominion scream Take me, you fools at you.  I think they've lost a lot of luster.

Having said that, these are dangerous units and one of the few ways you can bring 5 meltaguns to the party all in one unit.  If you are not using Repressors, and you have Rhinos instead, then they are a little more attractive because the transport is less points and you're not really trying to pack 6 meltaguns in, so 5 is pretty good at that point and plus you can ablate incoming wounds by taking full squads.  I really like Dominions even though this makes me sound like I don't.,  It was how I played early on in the codex.  The thing is, my results were 7-4 using an armored corps and all my wins and losses were marginal.  I had nowhere near the success doing it that I have now.  Can it be done?  Yes!  I won that way.  I did not win nearly as overwhelmingly though, and in ITC play, it does matter how much you win by.

Exorcist:  One of the least reliable tanks in Warhammer 40,000 and a notoriously bad idea if you only plan to take one.  Take 3 or don't take any would be my advice.  You need the numbers to average out the production and any Necron player will tell you how good a bevy of Doomsday Ark can be, which is kind of what they are.  Your enemies have become stronger, even since the Chapter Approved Sisters of Battle Codex dropped.  The new Space Marines look positively insane now.  I point this out because out-ranging the enemy is more important than it has ever been, given the silly amount of firepower people can wipe entire Sisters squads out with.  From the Scorpius batteries to the Leviathan to the copious numbers of Re-rollable this-and-that from Chapter Masters, the Battle Sister squads suffer badly from incoming fire (all the more reason to have more of them).  Battle Sisters are really most effective at 6"-12".  Outside of that range, the Adepta Sororitas are truly disadvantaged.  The Exorcist gives you something you really need:  ranged threat.  It doesn't even matter that they aren't reliable, because at the end of the day, the range gives you AT LEAST the chance to even the scales on the "killed More" side of ITC scoring as you stumble forward turn one.  It takes fire off of other units that can afford to take that fire less so than the Exorcist can.

I recently fought an ork (see last battle report) that obliterated half my sisters in a single turn...  Turn one!  When enemies can do that to you, through all their various buffs and shenanigans, you have GOT to be able to counter punch.  The Exorcists allowed me to kill enough of his strong but singular models to keep up on the scoring end.  So if for NO better reason than range, I like the Exorcists and they meant a lot to me in games against big single model type threats.  As you can tell, my list doesn't lack anti-tank at all even without the Exorcists.  I have boat loads of it.  However, it does you no good if you cannot reach anything.  That will be the case for a couple rounds!  Early rounds will be very impacted by having Exorcists present.  It makes taking Old School as a secondary more attractive, and it makes super elite armies kind of cry a little over the course of time.  Just know that they will disappoint you and not to rely on them for anything in any particular turn.  If your "master plan" this round starts with a sentence like"okay and then my Exorcists should be able to..." then stop.  Rewind.  And never say the word should again.  I will repeat:  they absolutely cannot be relied upon for anything in any given round. They are there because over time, and especially in the early two rounds, you just flat need the threat of that reach.  Just the threat of them will do a lot for you.

Retributor Squad:  These have been solid performers over the years.  The ability to take 4 Heavy Flamers and a combi-flamer is pretty boss, especially when delivered from Rhinos/Immolators.  Alternatively, being able to shoot 36" with heavy bolters gives you the range that Sisters lack so often.  Heavy bolters are also seen as a good way to handle the Ork menace on the come, standing behind the sacrificial first unit and blazing away in the aftermath to tremendously satisfying effect.  Space Marine Bolt Rifles and the like are rapidly taking away the advantages of heavy bolters for Battle Sisters.  The escalation on ranges in general is starting to be  damaging to the value of the Heavy Bolter Retributors, really.  As small units, they made more sense when it was work to get at them and shut them up.  Now they are getting shot turn one, just by a simple move by the enemy!  I really still like the flamer build.  Many flyer armies are being seen, and heavy flamers just don't care about your silly Hard To Hit rule.  If you add a Combi-Melta to the Sister Superior, you can make use of the Holy Trinity Stratagem, which is pretty nice on Retributors like this.

Heavy Bolter versions need to be used as a counter-punch probably.  I would just be cautious about deployment on them.  Hide them if it's an option and give them a chance to fire throughout the course of the game, and then they can rack up results for you.  Just look to making them maybe protected round one, and then have them come out after you know who is going first and where they will be.  Taking a -1 to hit turn one might not even be a bad thing considering you can use the Vessel of the Emperors Will Stratagem to negate the moving penalties for doing so.  A bevy of Heavy Bolters, if they are protected in turn one, can be a significant boost to long range firepower against a lot of armies; and withering to units who rely on vehicles who get popped.  Heavy bolters are really cost effective, and STR 5 is magical is 8E.

One other factor that does make them a little less cool is that there are now units that ignore weapon AP's of -1.  This is annoying, but it's a thing.  So consider who you're playing as to whether that might affect your use of them.  It's not a lions share of armies but it is a thing to think about.

Penitent Engines:  They have an abysmal history.  If it wasn't initiative in the old days killing them, it's something else.  These are light dreadnoughts with Dual Heavy Flamers and they advance an average of about 10.5" and then hope to charge.  They are getting 8 attacks if not interrupted, re-rolling to hit rolls, and they do have "Feel No Pain" on a 5+ which makes them tougher than they look, really.  It's 100 points of hope per suit.

Taking them in trios is what most people have historically done when taking them at all, to allow the inevitable attrition not to stop their overall mission of gumming up the works.  A little luck and you'll be demolishing units with the trio, and consolidating into more.  That is the theory.  This is more of a fun and fluffy choice for most armies and it will shock you with its efficacy if all three get there so it can be a game winning gambit but it is definitely a gambit.

Surprisingly, it really isn't affected much by Devastator Doctrines and its somewhat resilient against Psychic attacks given their Feel No Pain.  It is a deceptive unit.  In ACTUAL practice in the couple games I gave it the college try it failed spectacularly once and worked spectacularly once.  50/50.  If you are a gambler, the Penitent Engine trio can be a REALLY impactful play.  Just do it in more friendly games because at events where the super serious roam, 50%ish is probably not a great formula for winning overall.  But you will most definitely surprise people with them and you can see entire intercessor units vanish to their tender mercies.  Another piece of advice I would give, and this goes for many units:  don't heavy flamer the unit you're trying to charge most of the time.  Their attacks are plenty good enough to gank their targets.  You don't want to lengthen those charges too often.  I know it seems obvious but with an 8 inch weapon I think we can all recall a time when we kind of forgot that and in the game I failed in spectacularly with them, that was precisely the problem.  Turns out Heavy Flamers can do some work, sometimes too much.

Immolator:  It was the preferred vehicle for delivering min/maxed Dominion to the fight for a real long time.  Stuff a Twin Multi-Melta on it, wind it up, Vanguard move it up and watch it go.  It was also a great way, when the White Dwarf codex was out, to get the old Sororitas Command Squad up there.  Repressors are the clear choice if you own them, but given that its Forge World...  Immolators still largely dominated.

The Immolator is good.  It packs a great whallop for a l'il tank.  If you are min/maxing squads, there is no longer a reason to prefer Rhinos, as now neither allows anyone to fire from them.  Pop smoke round 1, and then start blasting round 2.  It's a credible threat and fast enough to get to Dreadnoughts and the like who do not at all like a little transport knocking them out, so it can divert important fire to itself rather than to your Sisters.  All in all a pretty satisfactory vehicle when and if your list needs them.

Since I prefer larger squads and less threat to the heavy weapons (and because bolters are absolutely still a good weapon), I don't make use of the Immolators in my list style.  Min/max'd squads will love them though.

Rhino:  Nuff said really.  It's great for larger squads and it CAN be made noticeably tougher with smoke launchers and the Celestine+ Indomitable Belief buff.  I will say that bringing dual Storm Bolters on these is economical and fun, and very worthwhile.  I am also a big fan of Hunter Killer Missiles and what the Rhino lacks in actual firepower it can make up for somewhat by carrying one.  When I played an armored list with primarily Rhinos, that is what I did.  There is a tactic among Sisters of Battle players called "Musical rhinos".  I didn't know there was a name for it but there is.  The Dominions jump out of them to blast away at the front lines while the sisters climb into the rhino from behind facing the enemy whenever possible wit hthe front of the tank, and then they replace the Dominions and so on, so the Rhinos become kind of a free movement buff for units behind them or around them, and a place to hide for a round as you approach when you're employing Dominions to wreck the enemy armor round 1.  Anyone who has faced Scorpius Batteries or other artillery armies will recognize the value of such a tactic.  If you are taking larger units, then this is also a handy way to get them forward after taking casualties because they will BECOME small enough units to get in after diverting enemy fire that would perhaps have been better spent on other units.  This can help you protect against the "killed more" ITC point sometimes!

Repressors:  Forge World.  Blech.  Fine, I'll go over this one also...  The main thing to note is that it allows you to load up a couple of squads of sisters and fire out of it.  The smartest play as aforementioned is 2 small Battle Sister Squads toting 3 Meltaguns each (you could also do flamers if that's your thang).  If I told you you that could buy a Rhino with more wounds, that had 6 Meltaguns ATTACHED to it, you'd drop a load in your shorts and have them immediately.  Same for a Chimera if it could do that.  Well that's basically what you're buying here.  Best part is that the Sisters of Battle can score objectives better and so when the tank blows up, you end up with min/max'd squads ready to rock someones world it comes...  no corresponding loss of firepower in the army (because normally the tank would take its weapons to the grave with it, but in this case, it doesn't!!!)  This is silly.  But most Forge World is silly.  The moral of the tale is if you wanna' really play armored stuff, you could do so much worse.

I think I hit them all.  I think the list of must haves are: St. Celestine, Canoness,  Missionary, Arco-Flagellents, and Sisters of Battle.

I think the highly advisable category includes:  Exorcists, Dialogus. Imagifier (index) and Seraphim
I think the "more than adequate alternatives, albeit not aaas critical" goes to:  Hospitaller, Death Cult Assassins, Repentia Sisters, Dominion, and Retributors.

The "do it if you like it fluffy" list is: Penitent Engines, Crusaders, Celestians, Geminaes"

I don't think transports really go into any category other than "potentially necessary".  Repressors are the best ones.  Immolators and Rhinos depend on whether you are min/maxing weapon squads or not.