It seems like the Last Jedi was almost good, and much like the original rough draft for Star Wars. With some edit using much of the materials, dialog redubbs, maybe one extra scene.

First edit I would've done was set the story with a time skip and Finn already up and running, with some pilot training. The initial battle scene could've been the same until the bombers arrive.

Add a new CGI scene where X-Wing breaks off perhaps to save Poe or chase after Tie Fighters, this leaves the bombers vulnerable.

Cut the scene of Finn waking up or imply that Finn got injured due to the Space battle.

Edit the demotion of Poe to where Poe is trying to cover Finn, and Lea wants to brig Finn, but Poe lies claims he ordered the Finn's mistake and he gets demoted. This makes Poe's demotion far more believable and keeps the scene largely intact.

We can leave Rei's jump back to but edit happen two years ago (or whatever decided the time skip), edit out the tossing of the lightsaber but Luke is still reluctant to train her.

Back when First Order finds the fleet, Poe runs to scramble his fighter, however instead of the Tie fighters blowing up the hanger, an explosion occurs destroying the fighters and this is largely to imply sabotage. The fleet can continue to run away, but a First Order officer ask to hyperspace jump ahead to cut off the rebel fleet, but get denied with that would ruin the fun or something to the effect.

Meanwhile Finn could look for a way to escape the fleet to warn Rei and the mechanic could accuse Finn to be the saboteur and when Finn denies it, she than accuse him of deserting. The rest of the scene could play out largely the same.

The casino scene could be left alone but have it so that both the mechanic and Finn could argue how and why they got arrested and complain that the "double parking" was silly. This can imply that one of the two is screwing up the mission. Returning to the fleet plays out largely the same with Finn trying to get back to the fleet.

Meanwhile Poe and the new commander could largely be left alone, but Poe has his suspicion that she is feeding the First Order information. And the Mutiny could be the result of both buying time and actually believing she intentionally screwing up the fleet. Lea stunning Poe could play out the same. Now the reason for keeping the cloak shuttles and the hidden base a secret because they fear someone informing the First Order of this plan.

The sabotage of the ship's hyperspace detection system fails in similar manner, and the first order now mentions they have a Spy working for them. And than we cut to the Slicer and saying order made a better offer but now with knowledge of spy they have reason to look for the cloak shuttles.

Now the turning of the main cruiser actually makes the fleet commander to look like the traitor. The attempted assassination of Finn and Mechanics could largely play the same. Now the slicer could mention he's going to leave now, because the ship's shields is gone to track the shuttles, and at this moment the rebel cruiser crashes into the ship and because the ship shields is gone this is actually effective, and the commander would've gotten the information of the down shields and knew something was up.

Meanwhile the training of Rei and improvement of her skills makes much more sense as she would've much more time with training. The reason for Luke could've stayed at the on the planet because he fears Snoke was actually controlling his action, and his attempt to murder Ben was because Snoke took control and he broke free.

The Salt flats could be largely the same, but this time it's Luke is the one that moves the boulders and stuff. Now I would say Luke survives, and makes a comment that he wonders if Snoke is actually dead or perhaps alludes to something else or pulling the strings.