One specific Boss in DS, and only for their Burst. Arcane Mage is pretty damn mid otherwise, Rogue is OK though.
On topic: We don’t fully know yet. It looks like Healer Wise, HPAL/DISC will be the go-to heal comp staples, and DPS wise Demo Lock, Fire Mage, and Ret Paladin will be in demand.
It’s hard to say what is good because you have Dragon Soul Class balance/design, but you won’t have Dragon Soul gear until late in the lifecycle. And as anyone with any experience in this game should know, just because you’re top dps at ilvl 360 it doesn’t mean you will be at ilvl410, or vice versa.
The most obvious answer is whatever is fun to you to play.
I remember that my frost dk was degraded two a three button class during cata which took away a lot of fun, so I would say wait for the cta pre patch, try every class you can get to try and decide then.
If you wanna go for minmaxing then possibly mage or rogue, yes.
If you aim for quick invites for dungeon finder… something tanky.
its important to know what you are aiming for at least since firelands raid - because you have to have your tarcegosa leggo if you want to join to hc raiding guilds in FL - so all people who will play :
I remember Ele and Balance being ridiculously good with the Legendary, but I don’t know how they pan out if they don’t have the legendary like in T11 or just in general. I do remember Rogue, Mage and Warlock were flat out just great though.
I main Warrior, Fury is RIP but Arms is going to be good in Dragon Soul, I have no idea how good it will be in T11 with much lower stats tho, no Gurth, different set bonuses and trinkets. It’s not like we have really good private servers to give a good idea, and those private servers for TBC/WOTLK have often been wrong anyway to, even the good ones, especially for TBC.
I only have vague memories of Cata tanking. But I remember my blood dk tank alt feeling really solid, especially towards the end of the expansion. I recall solo tanking DS, think I did all bosses as solo tank, but my memory could fail me here. In dungeons I was also a machine as blood dk tank, solid damage, loads of cooldowns to juggle, and lots of utility. Definitely felt like blood dk power spiked substantially from WotLK to Cata. The ability that put both diseases up at once without rune cost (Outbreak I think it was called) was a good addition that made a difference.
Edit: I can also add that my main class, resto druid, also felt solid and a good addition to any raid team for the entire expansion. The only time I recall struggling and eventually getting shafted to play my dps offspec was Baleroc in Firelands. Since resto druids largely depend on hots by design, they performed horrendously compared to other healers on that specific boss since the healing buff only stacked via direct healing. But that boss aside, I really liked how they play with the revamped healing system, and is what I’m considering maining this time around aswell.
Judging by the last cata private I played at (talking 10m, tanks would likely be the same for 25m, healing and dps would obviously be different):
Most guilds went for DK / feral tank combo (DK as MT for being god damn immortal and feral for obvious reason - hybrid spec does a very respectable dps when not tanking).
Healing combo was usually hpala + disc, alternately hpala + rdruid.
DPS…I’d say ret / arms as melee, rogues at DS tier for legendaries (not a bad class even early in the expansion though) and pretty much every caster is a machine with the staff, mage standing out dps-wise.
Cata’s issue is the 10m raiding - it’s more manageable roster-wise, but even with the class buff pruning, if you want to make a 10m comp covering all the raid buffs, you have one or two options (and even those differ in 1-2 spots). The “play whichever class you like” attitude that does somewhat work on WotLK (yes, there always are preferred classes, but almost every spec brings something and you want one of almost each) depends on raids having enough room for B and C classes, which 10m raids don’t have. Due to Cata ofc having preferred classes too, it might be hard to get a spot for certain classes - some just bring too little to the table to be worth a spot.
Thing is…I can’t be sure how the raiding community will handle the 10m / 25m raiding choice, perhaps there will be more 25m options than I expect (after all, 25m tends to be easier, on most bosses), so the roster issue will not be as big.
It will largely depend on how they implement the classes. I was around for the initial game, as many on this forum, and affliction lock was absolutely unbeatable by anyone in terms of damage, not -even- close, think 15% or so. The reason for this was the flat 15…20% dmg increase after casting soulfire. They then nerfed afflock to no longer profit from the soulfire buff, obviously.
But this did exist in the original cata, and the dmg difference was just like… being any dps class compared to the brown boys in vanilla.
Gotta think though, that they will take off with the -most balanced version- of Cata, and then I would think rogue.
Since thes introduced all the classic versions yet with the final patch class-mechanic wise, it is most likely that they would do the same with cata. So Class mechanics as in DS patch, no idea what this will do to the balance in the early endgame.
The bottom dollar will be either you have the legendary, or you won’t be considered for good guilds and won’t be able to parse. It’ll be highly mandatory in the higher end.
I happened to bump into a tier list on warcrafttavern, which somewhat surprisingly listed shadowpriest as top, which I do not remember so.
It’s not so transparant what was considered best in the past, but combining some info, I would guess at Afflock, UH DK, firemage, surv hunter.
Next tier shamans and druids, rets, the lesser mage and warlock specs.
Next tier warriors and rogues, the lesser shaman and druid specs.
This is a combination of some claims and lists here and there.