I truly don't like that they are cutting gladiator stance for prot warriors and crane stance for mistweavers.
Monk changes, on the healing side, are a bit "meh" so far, but I'll have to see how they change during alpha before saying something, for sure I'm glad they removed the fucked up mechanic of ReM+Uplift, which was shit with an UI mod and unplayable without. Well, you can throw Uplifts at random, but it wasn't nor interesting neither fun. The new spells seem interesting, especially the cleave heal. The artifact tree so far it's quite uninspiring to be honest.
Brewmasters so far haven't been pushed on the alpha build, according to MMO champion, but Guard, Expel Harm, Spinning Crane Kick (and RJW) seem to be gone. If they make Ox orbs similar to the Demon Hunter ones, then we could have a nice and interesting mechanic, if they remain random, then... shit. I know little to nothing about Windwalkers except that apparently we won't have the 2 specs limit anymore, or so I heard, in which case I may even play the spec from time to time.
On paper I like shadow priest changes, will have to try them in the field, but orbs weren't really that fun, so improving on them won't be too hard
