If Palpatine AI is on the table, there’s definitely things that can be done. His mouth isn’t visible for a lot of his dialogue.
In particular his first scenes with Kylo and Rey are ones where there’s space for exposition. If we’re trying to make the throne the source of power, there’s space in one or both of those scenes to spell that out - either subtly or explicitly.
One thing I’m looking at in particular is some sort of explanation for why Palpatine had her parents killed, which doesn’t really make sense. You could use for Rey Palpatine or Rey Nobody (depending on parental involvement).
Something like changing
"It is your birthright to rule. It is in your blood. Our blood.”
to
“I killed your parents to fuel the darkness in you. Through pain, I gave your life meaning.”