4) Alternative Reality
They have gone to all the trouble of creating an alternative timeline, why not use this opportunity to create new villains rather than trying to shoehorn in ones we have already seen? I know some people would love to see JJ Abrams take on Khan but whatever he does, it's always going to be compared to Wrath Of Khan and that is one thing that will do his film harm. So rather than struggle with that issue, why not just side step it and create something new to get people excited? The problem they have with doing that is that Orci and Kurtzman are incapable of writing a decent villain (like Nero demonstrated), so it's much easier for them to take an established character and redress him. But that plan will always fall flat because its like a shop that has a great window display but no stock to sell. And if they decided to create an alternative reality because it was felt that the other had gone stale, why insist on reusing all the same characters and invite comparisons? Don't make bold statements like blowing up Vulcan and then just end up remaking the previous films. So fingers cross Simon Pegg is telling the truth and Cumberbatch is not playing the genetically engineered super villain and they do try something new. Whoever the bad guy is, I hope he is more thought out than Nero was in the last film. And if they must use Khan, he would be better suited for the third film to keep the momentum going in the franchise. With the film due for release next year, I'm sure we wont have long to wait until some genuine information is officially released or leaked, which ever comes first.