They kinda zoomed past the complete restructuring of a civilization older than humankind: maybe there's a few kinks to work out? Also wouldn't mind getting to know a little bit more about how and why the gem empire came to be.
I also loved it, btw, especially the body-horror stuff.
I feel like SU is really good about taking time to decompress and examine the effects of events on the individual characters. I feel like the core three crystal gems kinda took a backseat in the last couple arcs, and I'd like to see them come to terms with everything before we close out, although I also feel very satisfied with it as an ending.