OK if you could travel in time why didn't Picard or Soran go back in time to before all their troubles began and make sure Soran and his family were off planet/ship when the Borg attacked or about a hundred other things that didn't involve destroying the ship...
Forget it. I could rant about this for days. Don't start me on Picard's or Kirk's greatest wishes.
And change 80-100 years of history? The only thing Picard could do without causing too much uncontrollable damage to the timeline was to go back in time to the point just before Soran launches the missile. Picard also didn't know that the Enterprise got destroyed. Perhaps if he had known that, he would have gone back a bit further.
The idea that he could go back to the start and arrest Soran before he did anything also doesn't work.
And besides that, how would Picard return to his time when he went back too far? He can't get back into the Nexus.
King Daniel Into Darkness wrote:
Whenever someone brings up STVI, I'm compelled to point out how horribly it treats the characters (Uhura doesn't know Klingon, Bones doesn't know Klingon anatomy, Kirk is suddenly a racist and they play the mind meld scene as if Spock is mind-raping a helpless, screaming Valaris in the middle of the bridge while the crew just stands around watching). Oops, I did it again...
Kirk's racism was more mistrust against the Empire, and has a emotional reason in his only son's death (David was killed by a Klingon claiming genesis for the entire empire, and it's highly likely that the Klingon Empire never ever apologized for it, so Kirk blaming all of them in his pain makes sense), and he overcomes it.
Spock was as disturbed after the mind meld as Valeris, which means he touched on a painful memory, he didn't cause the pain himself. The mind meld itself was absolutely necessary.
Uhura might have not known that particular Klingon dialect.