You’re right, the Palpatine and Ochi angle is a hard nut to crack, here’s what I propose:
Cut any connection between ochi and her parents, imply that his ship triggers her memories because its a similar model to the ship that Rey’s parents were on (the TFA vision looks slightly different anyway to the TROS model) From the start of the film she is tormented by visions of the Sith throne, flashbacks on Passana could be used in a way that only hints at Rey killing her parents, leaving the full reveal till Kijimmi, later in Kylo’s quarters you can change the dialogue to him saying"I pushed you in the desert because I needed to see it, I needed you to see it, What you did… Rey’s reactions to Kylo’s dialogue works perfectly as a reaction to the reveal, cut all the stuff about ochi killing her parents. As if that wasn’t enough, Kylo tells Rey that Palpatine has been waiting for them all this time, that he sensed their darkness since they were children, and declares that she is indeed a palpatine, that Kylo and Rey are a Dyad and that they will inherit the dark throne. (for this to work, Palpatine’s plan from the start should be to bring Rey, not kill her, so instead of “kill the girl” his dialogue to Kylo would change to “find the girl” “you will rule the Galaxy as Emperor and empress”)