Except for the following, very salient points:
1. Khan, as I detailed above, had every right to be harboring murderous rage at Kirk. His original sin in the TOS was basically to briefly comandeer Kirk's ship after Kirk woke his ass up from deep space slumber. Again, given his circumstances, an understandable reaction if not entirely aboveboard. Yet, of the DOZENS of races and persons who have successfully commandeered the Enterprise, ONLY Khan was subjected to a life sentence that at best equalled a hard life of backbreaking farming labor and probable early hardship and starvation, without benefit of technology, infrastucture, or even a sustainable population. EVEN had Seti Alpha not exploded, the chances for survival on the world were slim. Kirk had to have known that, which is why he conveniently never went back. Consider the reverse: Khan keeps the enterprise and maroons several hundred crewmen and Kirk on the same planet. After years of watching his people die on that rock, do you not think Kirk would have had murder in his eyes if Khan acccidentally wanered back into his phaser sights? Hell, THAT guy held a grudge over tribbles!
2. The detonation of the device, no matter what the motivation, would never have been carried out if Khan hadn't done it himself. Don't forget, Kirk and his ex and his kid spent most of the film arguing over whether anyone SHOULD detonate it, and without Khan would likely have remained in stalemate for years while everyone involved got oleder, the project lost funding, or some other factor rendered it obsolete. By detonating it on his own, Khan not only circumvented the entire tedious whiny argument but exposed key flaws in the device, which no doubt saved countless lives down the road. The fact that he got to kill his despised (and justifiably so) enemy was only gravy for his potatoes. Like he himself said, it was worth dying just to take out his hated enemy Kirk. This sentiment was echoed by KIRK himself on a number of occasions, for example in Generations when he allows himself to get killed in order to take out Malcolm McDowell and his dying question is "Did we get that fucker?"
3. Even if you disregard that Khan's actions provided the catalyst to save Spock, the fact is he didn't even kill him to start with.Spock committed selfless suicide by going in to fix the broken radioactive doohickey, and his situation had nothing to do with Khan's acts other than as collateral damage. Much like any faceless Klingon engineer might feel when his ship got blasted out of the sky by Kirk.
4. Khan even beats out Kirk in the morality department: despite years of hardship and certain doom, Khan stays faithful to his beloved wife and after her death raises their son to become a loyal and strong, proud young man, who willingly lays down his life for his dad; all this while presumably never marying again due to the memory of his lost love. Meanwhile,Kirk knocks up his girlfriend, ditches her to go tooling around space humping thirty years' worth of alien pussy as detailed in TOS, then FINALLY it occurs to him to check back in with her and find out he has a kid he never raised, never took a hand in guiding, and who fucking hates him. So who's the better man and father here?
No, Khan is not a villain in that sense of the word, and his actions were hardly as careless or disregarding of human life as those of Kirk. By all rights, we should have been cheering for him.
