Back to the topic of the original films: I've been re-watching the RIC, and I have to say I respect Lester's contributions a little more now. I prefer the Honeymoon Suite reveal to Lois-with-a-gun; and say what you will about the Amnesia Kiss, Kidder and Reeve's acting is superb there. A lot of the restored Donner footage reveals a discomfort about women (all those lines about punching Eve in the mouth!)-- not so much misogyny as gynophobia (if that's a word) that Lester's doesn't. And I agree that it just makes sense for Lara to advise Superman on matters of the heart.
What I'm coming around to is that there's probably no way to reconstruct the 'original vision' since that would be the 600-page script that was never completely shot. Scholars, weigh in here: if the time-reversal gag was the original ending, would Lois still have died at half-time? At the end? At all? It's fairly unworkable.
Sticking with II as a separate film, I say use the Lester cut as a guide because it has superior pacing and continuity, and because Ken Thorne's score actually fits the action. Cut back the comedy bits and the fake Lex, and re-introduce Donner footage where appropriate.