There was an idea on the Sequel Trilogy Radical Redux thread a while ago about swapping 8 and 9 that I was intrigued by. This would have had Palpatine as a clone made by Snoke to test Kylo. Attempting that was my backup plan if removing Palps from 9 proved infeasible.

So if I understand this, 7 ends right after the destruction of SKB with Rey still on D’Qar and Luke’s location still not found. Then we pick up with 9 (Ajon Kloss and D’Qar are identical, so it’s easy for them to be the same planet) and everyone is looking for the Wayfinder. To find Luke or to find the Sith fleet? Are you suggesting removing the Sith fleet entirely, or is Luke hiding out on the planet with the largest fleet of warships the galaxy has ever seen? If the fleet is still involved, I’m not sure how you would portray that it’s the same planet Luke is on. If the fleet is nixed and the Wayfinder is just to find Luke, that’s really going to cut the runtime down and it’s going to be a really short movie. Not to mention, Rey takes it from Kylo’s ship, so why didn’t Kylo use it to find Luke.

Swapping 8 and 9 also presents a problem with General Hux. You would pretty much have to remove him almost completely from one film or the other as he can’t be a spy before his actions in 8. His death would be easy enough to cut if he’s needed for a scene or two in 8.