Right, I currently play Rogue, Mage, Paladin and Warrior in PVP at the moment, so I have some experience with a few characters. Warriors are definitely the most powerful melee character I have, with Second Wind and Defensive Stance meaning they have better healing that a Ret in 5.0/5.1, but the buffs to Ret Healing in PVP Should fix that. Rogues are becoming godmode now, Cloak and Dagger is insane IMO, they aren't a great class now but they get the job done with gear, I don't think they need all the buffs they do for PVP. Mage has a nerf or two, so slightly more normal now, having also had the Frost Bomb and other nerfs since 5.0.
In terms of Warriors, the Defensive Stance for Arms/Fury is justified. It was the combination of Defensive Stance and Second Wind that gave Warriors such suvivability. Same with the Shockwave nerf, which made that Talent Tier mandatory for PVP generally. In terms of the changes to TFB and Overpower in 5.2, I think that's pretty odd personally. The overpower rage cost is pretty cruel, but I can't judge it in too much detail the changes to Slam, Heroic Strike and Overpower. The obnly issue Warrior have IMO is cooldown stacking. As a Warrior, you pop things and things die. That sums up how stupid I think Avatar/Recklessness/Skull Banner/Trinket are together. I like the Cooldowns, but stacking them is fairly OP IMO. Removing recklessness and increasing MS damage could be an idea which would improve sustained, which I would like.