Seriously, why couldn’t have Gary Mitchel been the antagonist if Into Darkness.  Other than Kahn , he is one of the few people Old Spock would have been fully in character saying “I don’t want to mess with the timeline, but seriously take him out.”  Cumberbatch with chromed eyes would have been a stunning visual.  And he can so play the arrogance of a wannabe demigod trying to shape the Federation into his view of “perfection”.