I think that the main issue with the game atm is class balance, I'm quite happy with the PVE side of the game but I'm firmly convinced that PVP will never be in a really good state until PVE and PVP are completely separated and tuned appropriately.
So, I'd separate abilities, stats, talents, pretty much everything that needs to be separated in order to balance much much more easily both aspects of the game.
---------- Post added 2012-11-30 at 11:29 AM ----------
Damn, didn't read it, you beat me to it...
Well, glad someone else agrees with me.