I think the second and third version of Luke and Ben’s nighttime flashback scene are not different enough.
2nd version: Luke tried to kill him.
3rd version: He was only about to.
I really hate to say it, but I’m liking this movie less and less as time goes on.
I think the three versions were great. And you’ve over-simplified the third one.
1st (Luke’s as told to Rey): Ben woke up and attacked.
2nd (Ben’s as told to Rey): Luke tried to kill Ben first.
3rd (Luke’s revised and presumably true version): Luke thought about killing Ben, for just a moment, after seeing the full darkness within Ben. He changed his mind almost immediately, but Ben woke to see Luke standing over him with a lightsaber and it was too late.
JEDIT: This…
Pretty sure Luke refers to it as “a moment of pure instinct”. It’s not that he was compelled by thoughts of temptation; he wasn’t thinking at all. And as soon as he does think about it he’s immediately overcome by shame and regret.