Only mentioning key changes:
The First Order is a militant organisation hell bent on destroying the New Republic and the last Jedi order.
Luke Skywalker is in hiding, post one of his students turning evil and destroying his monastery.
Rey is a scavenger in Jedha, searching for her lost parents. She gets off Jedha with Poe, Finn, Chewbacca and Han Solo who are in search of BB8 and the map.
Kylo Ren wishes to take Rey in as his apperentice after the interrogation.
Han,Chewie,Poe and Finn rescue Rey, but in mid conflict realize that Kylo is Ben Solo.
Kylo is forced by Snoke to attack the capital Coruscant and kill his father to complete his training.
Kylo and the First Order destroys the capital, and kills Han.
Rey fights Kylo with Luke's green lightsaber and manages to beat Kylo.
The Republic wins at a great cost and the message is sent about the power of First Order. Rey is sent to meet Luke and persuade him to return.
No Starkiller base, only a Pearl Harbor-esque attack with Star Destroyers, Tie Fighters and ground troops.
