****SPOILERS****
If this trilogy is about how anyone, no matter what your background, can save the Galaxy, then don't make Rey somehow become a Palpatine and make her change her last name to Skywalker in a completely unearned way. Let's not bring up the fact that the Skywalkers (the main characters and focal point of the entire Saga) lost and the whole Saga is disregarded in this movie. Let's just focus on this movie itself.
The entire plot is how Rey is actually related to the most evil person in all of star wars. She is afraid to admit this and denies this. This fear makes her angry and filled with blind rage. This starts to lead her to the dark side until the climax of the movie where she accepts who she is and stands next to Ben Solo (who is now the last skywalker). Ben just gets knocked off a cliff and survives just to climb up when the fight is over. He does nothing but bring Rey back to live after she does all of the work. They kiss (why?) and then he dies from healing her. She then goes on to call herself "Rey Skywalker" instead of "Rey Palpatine." She is still afraid to call/accept herself as a Palpatine. She is still in denial. She learned nothing, and all of the skywalkers are dead. A Palpatine won the galaxy....