The Keeper wrote:
Some people are griping that too much SS/TWOK made it into the film as is and you want them to have included even more, even at the expense of possibly losing screen-time for what was truly original in the film?
I don't know of any gripes about too much Space Seed. And really, at a certain point it didn't matter what you did with Khan, whether it was direct quotes from TWOK or a completely new story, people would still be calling it rehashing. So you might as well make the most of it.
And besides, a lot of the point of the OP was that he wanted to see a lot of what happened before
Space Seed. It sounded like it could be interesting.