Honestly, I think that it is Khan. The jump he did in the Trailer is the kind of thing that I would expect from an Augment. I originally wished it was Gary or Garth, but for the sake of argument, in the Trailer he is not really after Kirk, just like Khan was in TOS. He did try to kill Kirk, but it wasnt a personal vendetta.
And the girl is Carol Marcus! Why? Science insignia on the uniform (not rand) and Carol Marcus had a far greater weight on kirk's life than the other plausible characters.
So how old was David Marcus in TWOK? He looked like 24 or such, that would put him as being born on 2262. Quite close huh?