First off, all of the exotics should get the 330 damage buff from the update, not just the ones from Xûr!!! C'mon! They are supposed to be the best weapons in the game, but for some reason the Crotas End raid weapons and new DLC exotics are outshining the old ones. Is this just supposed to be a scam to make us buy the DLC? Guns like the Vex Mythoclast should get the buff too, even if you have to re-get the weapon. Either that, or Xûr should sell the upgraded damage form of all exotics, not just the ones he sells.
Second, I think that all the exotics should get the interchangeable damage modifiers, like solar, arc, and void that the new raid weapons do. This would definitely help them actually live up to being exotics, instead of being outshined by raid weapons, which are only legendary!!!