I have an idea for a more saga-conclusive ending. I think the Jedi from throughout the saga should return and stand with Rey to beat Palpatine. I think it could work like this:
After Palpatine says, “I will kill you” (or whatever) insert Luke’s “No” from TLJ, and then Luke in force ghost forms arrives standing beside Rey. This would be accomplished by masking a shot of him from a prior film, and then coloring it blue. It should be video, so it looks realistic, but possibly intentionally blurred so the mouths don’t have to match up to the dialogue. He then says, “A thousand generations of Jedi live in you.”
Yoda then arrives, with the force theme blasting. Next is Leia. Then Qui-Gon. Then Obi-Wan, possibly followed by an “hello there” if it isn’t too bathos. Then Mace Windu.
Maybe move the shot of Ben climbing back up here, if possible, so he’s included too. Finally, Anakin Skywalker arrives in force ghost form. Luke says, "No one’s ever really gone. Anakin says, “Master” (from throughout the PT) in a mocking tone to Palpatine, Palpatine responds with “no, no, no” (right before force lightning in ROTS).
And only THEN does Rey bring the second saber and finish off Palpatine, with the help of all the Jedi wronged by this evil Sith.
Next, for Ben’s sacrifice. I think the Jedi Force Ghosts should “save” Ben by transferring their remaining life forces. This would be done by showing the individual Jedi Ghosts disappearing right after Ben’s supposed death, and then reversing the shot so Ben comes back to life. You can then show Ben either on Acho-To or with Rey, with a reasonable explanation as to how they were able to both survive.