I would have put GF and II in chronological order, and included all of the deleted scenes. That version, called "The Godfather Saga," was shown on US cable TV stations for quite a while. That would have made an epic-length, but much more enjoyable, theatrical release movie.
If made today, I think it a pretty good chance that this would have happened as a miniseries. The big problem is that if you had eight hours or more, you might have ended up with the Johnny/Lucy chronicles included in the film along with all the stuff we want.
