I'm pretty inclined to agree here, actually. All the classes are doing well in arenas right now, and just about everything is viable. All 5 healers are strong, and all the DPS classes are viable as well. That alone is better balance then we've had in a very very long time.
The main problems with PvP right now is all the instant CC, or perhaps it's the lack of ways out of CC. I mean, if you had 2 PvP trinkets instead of 1 to break CC, maybe it wouldn't be so bad. But anyway, I digress. The point is that the things that are broken with PvP right now can't be fixed by one person. It'll require both the PvP and PvE designers to work together, because you need to remove CC from PvP but ensure that in PvE the CC isn't needed.
But honestly, this whole expansion has been pretty good from a PvP perspective.