Decanonize the Prequels. That has been my hope since these new films were made. Nothing is as irreverent as the terrible job they did on the Vader origin story. Arguably the worst origin story ever made, which is quite sad considering the character they had to work with. The sequels should all have been directed by the same director, and the overall arc should have been defined before the first shot was filmed in episode VII, but at least they didn't mess up anything as sacred as how Vader fell from grace.
I liked the prequels, they did show us how the empire was formed and made it clear that the Republic wasn't all roses and candies like the original trilogy give us the impression. For the political lore of Star Wars the prequels were fundamental. And really gave depth for that "evil empire", showing it actually came from somewhere and wasn't just there.
As for the new trilogy, I do think they made this terrible mistake of not defining an arc prior to filming.