I don’t see the end as an end. I see it as the beginning of something, but whether they have the courage to continue the main Saga is another thing entirely.
Rey is now the Last Jedi the same as Luke. Rey, Finn and Poe have to restore justice to the galaxy and restore the Republic. Rey needs to take on students and not repeat Luke and the prequel Jedi mistakes.
Maybe her order will be less dogmatic and accept a wider view of the force. She isn’t alone her family is Poe and Finn.
The story potential is amazing and they could do almost anything. But it requires directors and writers with a vision.
They had to know that when they took the reigns of Star Wars that their would be people who would question everything they did because they were not George Lucas. Would see every new character, every new anything really as invalid. The amount of fans seeing the sequels as a desecration is rather amazing to be honest. I mean its just a bunch of movies, not a religion.