Benecio Del Toro would have been a better visual fit for young Ricardo Montalban, I guess.
I think the problem with their portrayal of Khan was twofold; the first is the obvious racial issues, the second is that nothing he does in this story is in any way consistent with the iconic character we already knew.
I was also annoyed that when everybody guessed that Sherlock would be playing Khan, and they denied it to the press — they lied about it because they didn't fool anybody.
I liked the first JJ Trek for what I realize now were mostly nostalgic reasons, but the complete inconsistent mess that second one confirmed what people who didn't like the first one were saying all along. It definitely soured me completely on the direction of the franchise, and certainly instilled no confidence in me with respect to JJ's Star Wars movie.
Star Trek was always better on television anyway, where they could tell more character or idea-oriented stories, and don't always have to save the world and have hand-to-hand combat with the villain at the end.