I’d like to some PT aliens. Some OT aliens would be good, too. There are several characters I’d like to see in flashback, but they need to add to the story if they were to appear in the main story. I can’t think of any reason to do that.
I’d love to revisit any of planets. There were a bunch we only glimpsed. Coruscant needs to be addtessed, but I don’t much care if we see it.