It'll be interesting to see what they do for Episode 9. I can see Rey getting trained by Leia. But I don't think we'll get to see a ghost Luke. He shut out the Force until right at the end. How is it somebody that does that is able to disappear into the Force? Rey has no exposure to Yoda, so that probably won't happen either. Now you also got Carrier Fisher no longer with us, so unless they got absolutely EVERYTHING they could ever possibly need out of her, they'll need to do a Rogue One CGI fix on re-shoots. They really wrote themselves into a corner. There's only so much Rey can get out of the books she saved. Luke is out of the picture, Yoda is out, Leia probably won't be much help. If I were the writers, I'd have her return to Jakku and find her parents there. Plot twist that would make sense? We learn her parents are Ezra and Sabine from "Rebels". Now she can have a teacher (although Ezra would have to be old, like ObiWan was). Or we can discover that Ahsoka is still alive in some kind of extreme trance (suspended animation?) on some secret planet, and she trains Rey. As for Kylo, his inability to conquer Luke on his own terms drives him absolutely insane. He goes out and discovers Palpatine's secret cloning facility and makes a new Palpatine. Palpatine in turn destroys Kylo (I'd picture a snap of the finger and he just evaporates into dust or ashes). Palpatine then goes out and finds Rey, tries to convert her to the Dark side but fails. Then we learn Leia and Han had another child.....
Yup, fan theories are ALWAYS better than what will actually happen.