Palpatine is Rey's grandpa
Force ghost Han
Palpatine faces Rey in a gladiator coliseum with a star war raging above them, then steals the energy from Rey/Kylo's force bond to replenish himself for a lightsaber battle
The emperor being killed, the big death weapon being destroyed, a big galaxy wide celebration, ending with Rey making a lightsaber made out of Luke and Leia's and watching the twin suns on Tattoine