Interesting ideas, but it seems it’d be a little too much to pull off with merely audio changes. However, I think a ‘minimal changes needed to make Rey remain a non-Palpatine’ would probably be the way to go for the alternate cut of Ascendant.
What do you think of the sample clip someone did of the hanger scene where Kylo Ren tells her she will kill Palpatine and take the throne. Essentially, Palpatine wants her dead because he sees her as a dangerous threat to overrule him.