Okay, so I've been turning over the new Tau for a week or two now and I feel prepared to talk about them and how they compare with the rest of the current armies, at least from an armchair perspective. I don't think the prognosis for this army looks especially good nor do I think the army plays as it ought to. In this sense, I think this is one of the worst iterations of the Tau to date, right down there with 5th Edition (which was *the* worst).
To my mind, the signature units of the Tau are their battlesuits and the signiture playstyle is their ability to make pinpoint shooting attacks from mobile platforms that hobble the enemy before they get into close combat.
The current edition of the rules has seen most infantry get faster in several ways, has increased the ability to alpha strike, and made first turn assaults entirely possible. Vehicles (and notably transports) have gotten much tougher, making it much harder to prevent a close-quarters battle from happening. Furthermore, the capacity for assaulting units to tie up enemy units with consolidation moves is back, making close-order formations a significant risk and large assaulting units very dangerous to gunlines. It seems as though most armies need to find a way to make do in the charge/fight phases of the game.
The Tau Strategic Dilemma
In this faster environment with tougher transports and reliable reserves/deepstriking, as well as the larger divide between assault specialists and regular troops, the Tau, more than ever, need to be more mobile and be able to level greater firepower to survive.
However, Tau firepower has not increased overmuch. They have the distinction of being able to largely wound everything on 5s, but their access to high-AP weapons and multiple-wound damage weapons are rather severely restricted. This, coupled with the fact that markerlights are less powerful (if more broadly useful) and the army has no access to any BS better than 4+ apart from Vehicles, makes the Tau shooting phase less effective than in previous editions. We're basically shooting like we did in 3rd/4th Edition, which would be fine but for the fact that other armies are doing better in this category than they were.
Furthermore, the Tau have lost some maneuverability thanks to the elimination of Jump-Shoot-Jump, which has been replaced with the Fly mechanics. This don't help much, since they are predicated on the fact that the Tau unit in question survives combat in the first place. The Tau are not much good at this.
I'll start with some of the good news first.
Strike Teams have gotten a little cheaper and shoot basically as well as before (minus easy access to BS boosts). The loss of the pinning mechanic, while never crucial to the Tau gameplan, is a notable blow, given than it was very useful when it happened. Photon grenades are objectively better.
Breacher Teams are arguably worse than they were before against MEQs, but substantially better against TEQs--your metagame probably dictates whether this is worth it or not. Their problem--that of mainly having to get super close to do their best damage, but that damage not being sufficient to prevent them from being wiped out immediately thereafter--hasn't gone away at all. Because you can't arrange for them to be boosted to a 2+ BS easily anymore, that problem is arguably worse. They're a bit cheaper, though, so that's it.
Pathfinders are dirt cheap now and that's good, but their markerlights, as mentioned, are only "meh." Their special weapons are overpriced, but given the choice between equipping a Pathfinder or shelling out for a whole Crisis Suits, the Pathfinder sounds damned attractive. I generally like these now. One possibly beneficial side-effect of the markerlight nerf might be that people don't shoot them off the board turn one anymore.
Kroot are legitimately terrible now. What once made Kroot very useful--their infiltrate ability, field-craft, and boosted cover saves--are all gone now. They don't even have access to sniper ammo anymore. About their only role is as cannon fodder or assault buffers. Certainly an important role, but I've never really liked paying points for units that will do no damage and die outright to a stiff breeze. Cover barely even helps them anymore. Blech.
Kroothounds are ostensibly the only thing in the army definable as a "counter charge" unit. They are really bad at it, though, and compete for Fast Attack slots which are already competitive. You need lots and lots of these guys to work. I do, however, like them a bit better than Kroot themselves.
Shapers are every bit as worthless as they've always been, which is saying something. You'd think they'd finally give these guys a tactical purpose besides "I desperately want to waste the cost of 5 Kroot on a guy who makes my Kroot "braver." As if Kroot ever take anything but massive casualties that would result in the unit being wiped and isn't that the only point of Kroot now, anyway, so what the hell are we even doing?
Krootoxen are overpriced autocannons with a worse statline. They hit reasonably hard in assault, but why anybody would expect them to survive long enough *to* assault is somewhat suspect. Basically you need to buy the assault abilities to get the gun, but don't really want to use the assault abilities because then you will probably lose the gun you wanted in the first place. They have the distinction, however, of being the cheapest platform for heavy weapons in the army, so there's that.
Vespid are the shining stars, here. Fast, tougher than before, better shooting, good deployment options, and cheap as chips for what they do. I like these guys (though I don't like the models) and can see taking a bunch of them.
Devilfish are mostly okay. They are about 30-40 points more expensive than before, but are suitably durable to make up for that. Smart Missile Systems are no longer worth it on this tank, though, since you want it to move all the time and paying for those shots at a -1 BS is not a good bargain. Better to take the drones.
Piranha doubled in cost and got a *little* more durable. Firepower, on balance, remained static. The overall reduction of the effectiveness of melta weapons (i.e. no one-shot kills anymore) makes them less attractive fusion blaster caddies. Kicking out a ton of S5 seems mostly what they're good for, but you can get that for cheaper elsewhere.
Hammerheads have returned to the cost of the old 4th/5th edition tank. Their firepower is about the same as it was back then, too, but the tanks can't quite move as easily and still fire their main gun at full effectiveness. The railgun solid shot is okay, though they special ability is mostly just a gimmick (2 extra wounds done once a game? Meh). The cost of the ion cannon vastly outweighs its efficacy, so I kinda doubt those will be seeing much play. Likewise, the Railgun submunition took a pretty hard hit (like most large blasts in the game). I would provisionally say these tanks are still worth it in the absence of any other D6 damage weapons that have a good BS. It's a lot to pay for the privilege, though.
Skyrays have sunk considerably in my esteem. First is because markerlights are really only good en masse, and this tank costs about as much as a Hammerhead for two of them. The second is that their seeker missiles are only so-so. Yes, they're mortal wounds, but they're only one shot each. 6 mortal wounds do not a game win. Hell, they won't even blow up a transport.
Here is where the army gets kicked in the teeth and I don't quite understand why.
Stealth Suits are approximately as good as before and cost about the same, though the fusion blaster is wildly expensive. I can see using a bunch of these guys.
Crisis Suits got insanely expensive for no particularly good reason. They are modestly more durable, but this is readily counteracted by the loss of their jet pack move. The support systems are lackluster and their weapons are overpriced with the exception of the Burst Cannon. The stand-out here is the missile pod which, despite it's autocannon-esque statline, costs 10 points more than all other autocannon clones out there. Furthermore, you *have* to take 3 of these guys--no more monat suits. The costs are prohibitive (doubled what they used to cost), meaning you are fielding half the guys you used to and they really didn't get *any* more shooty. The only offensive benefit is firing three weapons at once, but at the weapon prices we're paying, that just means fewer guns overall on the board. This wouldn't be so bad if Crisis suits didn't play such a crucial role in the army--they're only real platforms for special weapons we have. I am a total loss as to why they needed to be priced this way. I mean, Christ, you could have at least sprung for a 3+ BS for a unit that is a shooting specialist in a shooting specialized army. When I compare these guys to what other armies can get for the same cost, I cry real tears.
On that note, Riptides have become prohibitively expensive to the point where they are basically unfieldable. They follow a similar pattern as the Crisis Suits: modestly more durable, but same firepower and weaker weapons in the new environment. Is there any godly reason the Ion Accelerator should have a 3-digit price tag? I can't think of one. The Heavy Burst Cannon is the way to go, but even that is pretty lame for what you pay. Oh, yeah, and the Nova thing just automatically does wounds, so I guess the Earth Caste technicians have regressed a step or three.
Ghostkeels are probably the best deal for suits in the army at the moment, weighing in just north of a Hammerhead and having decent weapon systems and area buffs that will pair very well with Stealth suits.
Broadsides are also super expensive for reasons not entirely clear. The Heavy Rail Rifle is a good gun, though, and maybe worth taking. The point to power ratio here, though, is really bad.
Stormsurges cost about what they ought to cost, given all the guns they're toting. What is crazy is that they aren't *that* much more expensive than a Riptide, but are tougher and have triple the firepower. Go figure.
I'll come back and finish this later--all I need to talk about are Drones and HQs, but it's late and I'm tired.