Though It's a wonderful captivating space-realm sci-fi movie plotted in the far future 2295A.D. I noticed elements highly incompatible :-
1.It was said that Khan & his crews were genetically modified 300 years ago to be a super genetical breed. 300 years in past from 2295A.D. is utterly in the year 1995. According to the movie,a powerful mercenary ,having cell regeneration ability (actually immortal in a way) can easily defeat almost all the technologies of 2295A.D. & was created by the technology of 1995..
2.If the science of human immortality was founded 300 years back(accepting the movie plot)then why it remained hidden for 3 long centuries?Khan is also of this planet.
3.Kirk sacrificed his life in the high magnitude radiation chamber & he was brought back to life by cloning the regenerating cells of Khan .Wow !
GOOD NEWS:- now no one from 2295AD. will die out of radiation ;human kind gonna be immortal