Why couldn’t they have kept Space Sherlock as John Harrison? Here’s how simple this is: it’s an alternate timeline. In the original timeline, Khan was the one woken up. In the new Abrams timeline, Harrison was woken up. Maybe John Harrison was Khan’s First Officer, I don’t know. Not like that would go with the theme or anything. It’s assumed that all 73 of those bozos are equally as strong and evil. Then when Spock ring a ding dings up Spock Prime, Nimoy can be like “I don’t know a John Harrison but that does sound an awful lot like this dude we know named Khan…”



I saw someone else comment that, if Harrison had been Khan’s second in command, part of the villain’s motivation could have been to awaken Khan.  Khan could have been the unseen, epic legend the villain mentions (plus whatever Spock prime wanted to say).  It would still be problematic (since Khan wouldn’t be seen and thus a white character would take the place of a character of color) but at least Khan wouldn’t be whitewashed.  I think that storyline could have been fascinating.