I have no idea. Seriously, how could I possibly know what you want to see? I mean, you might tell me in the comments, but that's in the future. There's no way I can have read the comments on this post before I finish writing it. However, I'm fairly in touch with what I want to see. And so, here's five features I wish WoW had. (Note - I didn't say more bank space or void storage tabs, but man, I want those too.)
One of the features the lamented MMO City of Heroes had that I always enjoyed was its Mentoring system. Now, this isn't something WoW's developer's are unaware of - it's a fantastic system which allows higher level characters to play with their lower level friends, either by raising the lower level character temporarily in order to be able to survive higher level content, or by lowering the higher level character to the lower level. The current system that can raise or lower gear levels for beta testing and which will normalize gear for challenge modes could be used in such a fashion, and I think it's an idea long overdue for WoW to blatantly pilfer and run with it.