It would certainly add to the spontaneity of the gameplay, as public events are really the only thing that aren't scripted in the PvE side of the game. Having some rare world bosses for people to have a go at would likely make gearing up more interesting! I'd like these beasts to be difficult where necessary though, such as having attacks that need to be avoided rather than just big health and damage numbers, as well as phases and strategies that need to be heeded well to. If that's the case, I'd be more than glad to spend the extra time needed to get myself some juicy loot!