I haven't read the rest of the thread, so apologies if I repeat something.
I always liked this one, and watch it as much as any other Trek film. I especially like the moment where Kirk decides to go to Genesis during his meeting with his superior - he says nothing, but you can see that switch going on inside his head, A fine, fine bit of acting from Shatner.
And as for the famous line "My God, Bones - what have I done?" - I'd have loved it if there were no more dialog for the rest of the scene (I hate the line that Bones has). Just silence as the Enterprise burns up.