If and this is a kind of big if the old leak was correct and we are getting a base level boost to level 30 I'd expect that each of the existing classes might get a few new abilities with that. It would bring the current Max level to 44 which would put us at a serious advantage in things like Vault of Glass. But then the Vault does have another set of armor we have never seen which could drop on VoG lvl 44. Who knows how big The Taken King is going to be.
Really?