I think I'm one of the few the enjoyed the Rey Palpatine twist.

It inverts the Skywalker saving a Skywalker from a Palpatine to a Palpatine saving a Skywalker from a Palpatine, which was a nice bit of themetic nuance for me. Granted, I wish they set it up & executed it better but I digress ... It was a good idea.

Rey Nobody I think would've worked had they continued down the path of rejecting what came before you. If Kylo is revealed to be the one that killed her parents at Luke's temple and drops her off because he feels guilty murdering a child because he doesn't want to be a full-on Vader (and blocks her memory), I think Rey Nobody works. And he would still need to turn to the light to bring back Rey from death IMHO for that arc to work as she dies trying to stop the big bad.