Shit. I just teared up watching your clip of the last 5 minutes. Beautiful job bringing the whole saga to a close. The prequel music is so welcome in this movie-- this is the first "Prequel movie" in a way because it's the first movie they made knowing Vader would be a "good guy" and that everything comes back to that. Until ROTJ, it was two movies about Luke. With ROTJ it became 6 movies about Darth Vader. So excellent job making that work.

I thought you were going to put Vader's death after the DS2 explodes. I'm not sure I want that, but one thing that always bothered me is how fast Lando gets out of DS2 compared with how long it takes to get in.

Have you tried putting Vader's death right after Lando shoots the core and starts his escape? Then after Vader dies, it will feel like Lando has been escaping the appropriate amount of time and he'd better get out fast or die.

EDIT: I also want to say I really appreciate the thought you're putting into this. Keeping stuff you don't like to make the emotional story work is exactly the right attitude, I think. The impact is already showing up in the clips you've done.