I have an interesting idea/premise.

Rey from the Force Awakens/The Last Jedi meeting Darth Revan. For those who remember playing Knights of the Old Republic, he was the main hero/villain of the story. We never really got any conclusion to what happened to him, but there's many theories and I have my own.

My theory involves Darth Plagueis (Mentioned in Episode III By Sidious/Palpatine) and Revan's Apprentice. Plagueis was the Apprentice of Revan's apprentice who convinced him to turn on Revan, containing him in ice on Hoth as a way to keep him out of the war that was going to ensue but also to keep him from foiling the plan. Plagueis then killed his master and got his own Apprentice, who we assume was Palpatine, and then was struck down. Obviously to become more powerful than ever, and to learn the secrets of the Force, Palpatine returned to Hoth to drain the force from Revan and grow even stronger. Well, with his death Revan's powers would be back, but he wouldn't be at full strength due to being frozen for a near 1-2 Millenia. 

Rey would get a vision of a powerful Jedi, Revan, and see him on Hoth trapped in ice. That's how the story would begin, with a lot more detail and thought mind you.

Any takers?

For anyone who doesn't know about Revan, I shall leave a Wiki link below but with a warning.

I do not play characters 100% canonically. I change them to suit my needs/desires. 

[url]starwars.wikia.com/wiki/Revan[/url]