I like a lot of your ideas! I also like the idea of Ben Solo surviving in the end. It’s personally an edit I would like to see made after Rey Nobody is accomplished.
This all came back to my mind recently because the Templin Institute on YouTube posted a new video reimagining the First Order-New Republic War. They kept things closer to the films than I thought they would. Definitely some deviations, but the big story beats are still there. The major difference is the details they chose to add. Some interesting takeaways:
• The Resistance is one of many “volunteer forces” that work for the New Republic.
• Starkiller Base is still a new Death Star, but with the caveat that it can only fire once. I’m not sure how you could get this idea across in the film. Maybe new dialogue from a Resistance officer or pilot during the briefing or the attack.
• A huge chunk of the New Republic fleet was at Hosnian Prime to celebrate the anniversary of the battle of Endor (not sure if this could get across in an edit at all).
• The entirety of the New Republic military wasn’t destroyed in the attack. But the days/weeks following, the remnants were scattered and struggling to fight off the FO’s coordinated offensive.
• Leia becomes the de facto leader of an emergency New Republic government.
• The battle of Crait and the duel between Luke and Kylo Ren is broadcast to the galaxy as a propaganda tactic that blows up in the First Order’s face.
• During the TLJ-TROS interim (which is 5 years), the New Republic/Resistance makes efforts to gain allies and rebuild/reorganize a new New Republic fleet. So the final battle isn’t “just people” per se, but a makeshift armada under the leadership of the New Republic.
I feel like if one were to try to work with this approach, the crawls would do a lot of the legwork, but perhaps off screen radio communication with the Resistance “allies” or the TROS civilian fleet could be replaced with dialogue that more clearly depicts those entities as New Republic.
So the scattered New Republic fleet is simply too busy to help the Resistance in TLJ rather than being too afraid to help. And then in TROS, cut dialogue that implies the Resistance is still all alone, and use the crawl to help explain that efforts to rebuild the New Republic have been underway.
EDIT: Here’s a link to the video https://youtu.be/0Ai--LPeKQQ