It was a bit disappointing to have my pet fan theory - that Rey was Anakin reincarnated - shot apart.
Rey being Palpatine's granddaughter doesn't work quite as well... unless, as was implied in Ep 3 and Ep 9, Anakin (and thus the Skywalkers) was Palpatine's creation. In which case the final dyad of Rey Palpatine and Ben Solo-Skywalker destroying the Sith together does close everything up rather nicely.
Luke wasn't entirely wrong to have gone into seclusion. It was time for the Jedi to end. There is a heavily anarchist subtext running through the third trilogy - all through VII and VIII I kept on wondering what's going on elsewhere. What's happening on Coruscant? Corellia? Chandrila? Dac? Eriadu? Kuat? Raaltir? Kashyyk? Malastare? Ryloth? There's this whole galaxy of major Republic/Empire worlds that don't seem to have much of anything to do with this conflict. They destroyed the worlds of the Hosnian system... which had never even come into the story until the same movie in which it was destroyed (admittedly the same could be said of Alderaan at the time Ep IV was made, though it was relevant to the prequels). As one of my friends said... "maybe the galaxy has decided to go on without them"? (Them being the First Order and the Resistance) "Perhaps it's a 'war in heaven', like in Stellaris?" (For those who have never played Stellaris, a War in Heaven is a great conflict between two very advanced ancient empire factions... which often doesn't have much impact on the majority of the galaxy.)
Ep IX confirmed that. "It's not a navy... it's just people." A bit of a cheesy line, but it worked. The huge armada that arrived were traders, local militias, bounty hunters, adventurers, private militaries... the minutemen of the galaxy, who no longer need the Republic, the Empire, the Jedi or the Sith.
Just people. The galaxy can now go it's own way and move on from 10,000 years of stagnation.
That didn't retcon or reject Ep VIII in any way... that confirmed it. It was a rebirth.
To me that was the most brilliant thing about this movie. My problem with the Expanded Universe was that it was a universe locked into the same conflict, the same story, over and over again... fought by the same people.
Ep VIII AND IX said... that ends right here.
Balance was restored to The Force. The Galaxy was liberated, at last.