Has anyone considered the feasibility of removing most of the flashback scenes altogether? There are a few reasons for this, one being that Star Wars movies have never had straight-up flashbacks (even if these are colored by Point of View).
Also, since most people who take issue with Luke cite his brief murderous intentions toward his nephew, it might work to present a more enigmatic version of events. Here’s one way it could be presented:
Remove the first flashback from Luke’s perspective. Have it go from
“By the time I realized I was no match for the darkness rising in him…It was too late.”
to
“Leia blamed Snoke, but…It was me. I failed. Because I was Luke Skywalker. Jedi master.”
This makes it sound like he simply wasn’t a good enough teacher to stop Snoke and his influence. Although if the issue is not the flashback itself but Luke’s behavior in the hut, it might be good to keep the entire recollection, just minus the shot of inside Kylo’s hut. This way the entire flashback could be viewed as correct and not tainted by Luke’s point of view.
Next, move Ren’s version of the flashback until after the Darkside cave, when they are communicating in the island hut. Then the flashback can be played as a Force vision from Kylo to Rey:
“He sensed my power…as he senses yours. And he feared it.”
Show Kylo starting awake, and seeing Luke standing over him in the darkness with a crazed look on his face. Out of self-preservation, Kylo pulls his saber to him. The green saber ignites, then Kylo’s. There is a clash of blue and green, then the hut collapses. Suddenly a vision comes to Kylo and Rey of the throne room, and of Kylo holding out his hand. Rey reaches out to take it, and in the island hut their fingers touch.
Luke interrupts this revelation as he does in the movie. Then the rain battle could stay as it is, or she could knock Luke down quickly without wanting to know anything more about Kylo. In either case, there is no flashback from Luke. Rey is more interested in telling Luke her vision of the future:
“There is still conflict in him. If he turned from the dark side, that could shift the tide. This could be how we win.”
“This is not going to go the way you think.”
“It is. Just now, when we touched hands…I saw his future. As solid as I’m seeing you. If I go to him, Ben Solo will turn.”
These changes might clear up a lot of the character inconsistencies in the movie. Luke is acting in character by nonviolently confronting Kylo about the darkness he has sensed within him. Kylo is acting in character by being surprised and frightened by Luke standing over him in his room at night with a look of horror and fear, and responds through simple self-preservation. The quick escalation is understandable and tragic, and Rey understands that there wasn’t time for Luke to turn Ren as he did Vader, and has decided to do this herself since Luke is too consumed with his failure.