With Blizzard changing so much with PvP gear and how it works this expansion, I think it is finally time to just outright make PvP gear seperate from PvE entirely. All instanced PvP would swap you to your "PvP set", which would start out to be equivalent to the current crafted PvP gear, and than upgraded through Honor/CP as normal. Now we can balance the classes with just this PvP set in mind. Heck, it even gives a nice dial to turn if a class is being to dominant. Hunters doing to much damage? Lower the PvP Power on their armor. Similar to the way they could reduce base Mastery like they did to Frost Mages, but only affects PvP.
The biggest issue I have always had with this myself was world PvP. But in all honesty, wouldn't it actually make world PvP MORE fair? Currently if you don't have PvP gear you simply just don't stand a chance in World PvP. If everyone was in PvE gear (which if you are out in the world, you will have a PvE set anyways since you are fighting NPCs) you wouldn't have those situations. No more worrying about PvP Power and healing out in the world. Keep the 65% base resilience however, even out in the world.
The one issue I have is that it would destroy any semblance of cross-activity benefits. Amazing raid gear would give you absolutely no advantage when you are starting to PvP, and vice-versa. There could be a way to take care of that though.
I do think its finally time for such a thing though. PvP gear and the systems behind it have been a roller coaster for some time now, and this would finally normalize it.