I watched Rogue One: A Star Wars Story for the 3rd time this morning. Something still bugged me despite me enjoying it even more for a 3rd time.
Then, it clicked. An important moment in the movie features a Hammerhead class corvette.
Why is the ship class important? That design originated in Bioware's Knights of the Old Republic (2003) with the Endar Spire -- the first thing seen in the game. It was brought out of Legends and back into canon... from the most praised video game story in the Star Wars universe. (Technically, it reappeared in Star Wars Rebels first, but I don't know what its canon status is for certain. ... I also have not seen Star Wars Rebels beyond some previews before the show was released.)
I can't help but wonder what else could be brought in from KotOR. I cannot imagine how they'd bring in the entire story out of Legends status without simply acknowledging the game as canon and leaving it at that. To reboot it would be a disaster in my opinion. Since no Star Wars movie has ever (nor will ever) come from an existing story (game, comic or novel), there's no chance that we'll see it in movie form unless it's rebooted which, again, would be a disaster in my opinion.
As for KotOR 2 elements coming out of Legends status, I want it rebooted without any ties to Revan's story and figure in the concepts of the Triumvirate's "wounds" against the Exile's "wound" instead of merely mentioning them and settling for boss battles. Given how tedious the fights were in KotOR2, I figure it would make a nice Telltale-style game instead. I will iterate that the concept of the story could (and should) stand on its own without Revan.
By removing all coattails of KotOR for The Sith Lords, a reboot makes more sense and is more possible in my opinion. Otherwise, make it a movie reboot. I think that there's enough there to make it work and be different enough to be a new experience without the whole "no pre-existing story". Just stick with the premise of the Triumvirate and the Exile and start over -- something that wouldn't work well for Revan's story. If they can do that with Thrawn, they can do that with The Sith Lords.