Have Rey be Palpatine’s granddaughter, and he tries to possess her.
Have Palpatine be back with absolutely no explanation.
Give Palpatine a fleet of planet destroying Star Destroyers with absolutely no explanation.
Give Palpatine a bucket of Snoke clones as a reason for Snoke’s existence.
Have Palpatine reveal that killing him will make him win right as Rey is about to kill him.
Have Palpatine change his plan no less than three times.
Have Palpatine’s minion kill Rey’s parents instead of taking them to Sheev for interrogation.
Have Rey’s parents say ‘She’s not on Jakku’ and have this actually work.
Have a scene set on a visually dramatic lava planet but constrain the action to a flat section of burned forest.
Introduce a map mcguffin but have it be found and used immediately by the villain, requiring the introduction of an identical copy of this mcguffin for the heroes to pursue, then a contrived reason for the villain to pursue the heroes instead of just waiting for them to find the second mcguffin and arrive at his location, which is what he wants to do anyway.
Give Chewie a fakeout death but almost immediately reveal that he is still alive.
Give enemy ships a new ability, then concoct a novel way of countering this ability, then cut the scene where all of this is paid off.
Retcon Leia as being basically a Jedi who does practically nothing with these skills for the rest of her life.
Have Leia communicate with Kylo through the Force and help redeem him at the cost of her life, then cut the communication bit so it looks like she dies for no reason.
Have Kylo hallucinate an image of his father, and have this appear to be what redeems him.
Cut Finn’s presence in the film down to ‘Fails to deliver a line’.
Make a point to give the Latino character a background in drug smuggling.
Give Poe a character arc in which he is burdened with the responsibility of leadership then cut any scene where it is displayed.
Give Threepio a complete memory wipe so that he can translate some data which was in his memory.
Trap characters on a doomed planet, but then have those same characters show up later with no explanation for their escape.
Introduce the concept of a ‘Force Dyad’, which means that when Kylo and Rey are together they have the amazing ability to be so strong that their power can be instantly drained from them by Palpatine. Since Kylo is required to be present for this to work, make him arrive on the planet via a standard TIE fighter, one specifically without a hyperdrive.
Cut almost all scenes of the Knights of Ren doing things.
Cut Rose.
Make a point of placing the ruins of the second Death Star on a planet which isn’t Endor, just to confuse people.
Make the most fanatical devotee of the First Order betray this organization because he doesn’t like the way its leader chews his food, or something.
As a symbolic illustration of Luke’s freedom from his exile on a remote island, cut his part to 1(one) scene which is constrained to only this island.
Make the villain’s planet both notoriously hard to get to but also extremely easy to get to by thousands of ships from across the galaxy.
Give the dangerous planet-destroying fleet the small weakness that without constant external guidance they will just crash. Also make their primary weapon unshielded and so poorly made that destroying it will blow up the ship.
Rule the villain’s defeat a suicide due to being very bad at his signature attack.
Set the final scene of the movie on a planet nobody in this universe cares about and has little meaning even to the main character. In fact, cut mention of any well-populated planet and make Bespin and Endor representative of the entire galaxy.
Call the movie which kills all the Skywalkers ‘The Rise of Skywalker’.
“Just when I thought I was out…they pull me back in”