Lol dude lay off. TBN is literally the best mitigation in the game and the reason Dark was the best boss tank for most of EW. The problem is we got screwed on mana regen, less mana = less tbn = significantly less mitigation and less dps.

Right now Gunbreaker continues to be the best tank DPS, as it was in EW, and might have been in ShB too I don't recall. Either way everything past that is meaningless. Best Tank DPS = optimal for all savage as a second tank.
Paladin currently has the best mitigation, which means they are the easiest to keep alive. Best mitigation = best main tank for savage.

Warrior is in the same place it was in EW, great is newb friendly dungeon, not great in the hard content. Self heals don't matter in savage. Dark sadly went from being probably the toughest dungeon tank but great in savage to just being sub optimal all around. But again, if we get our mp regen back that will help with this considerably.