When it comes to the feast I can't really say, as I've only played a few matches.

But in frontline, DRK does not need a buff. They do fine without any invincibility. It's probably the most op tank atm despite that.
BRDs and MCHs are also op in frontline.

I'd like to see them buff WAR at least.

Best thing would be if SE deleted PvP 4.x and rolled it back as it was before expansion.