Khan was probably the greatest villain in all of Trek...and people are bitching about him (possibly) coming back?
I guess I'll never understand....
I happen to be one of the people who don't find Khan to be a particularly interesting, complex or compelling villain. He was one of the several more or less memorable villains from TOS, he was in one solid episode, and then, yeah, he happened to be the villain in an excellent Trek movie. But while I like the movie, I don't think that he was the main reason why the movie was good. He was a convincing adversary to Kirk, but I don't see what else is there to explore about his personality or why I should find it interesting. And I certainly don't see what new and challenging things could be done by rehashing his story.
Unless they do something really radical, like making him Kirk's ally this time, but I'm not sure how that would work.
Otherwise, if it is just a rehash of the old story, what is the point?