In Inheritance, the scene opens with Princess Arya (Leia) taking Saphiras egg (plans) to the Varden (rebels), when her caravan is taken by the Urgals (troopers). Arya sends the egg away to Carvahall (Dantooine), ostensibly to Brom (Obi-Wan), a fallen member of an ancient group of peacekeepers, who lives there. So, Saphira is sent to Carvahall and is incredibly valuable to both the RebeVarden and the Empire. It is only through sheer happenstance that Eragon happens upon her egg.
Eragon then travels to Helgrind (Alderaan) and picks up a friend on the way, Murt (Han).
In both, the mentor and ex-Rider/Jedi is killed defending their charge.
In both, once the main character joins the Rebellion/Varden, there is a battle and they are visted and told to go to visit Yoda/Oromis for true Jedi/Rider training. In both, the mentor is old/sick. The mentor trains them, but then the protagonist descovers his friends are in trouble and is forced to abandon his training. They leave, promising to return and complete training. I believe that oromis will die when Eragon returns for training.
Then they are confronted by a hitherto unknown family member, they lose their weapon and learn that the Emperors right-hand man was his father. The fact that Paolini switched father for brother seems rather irrelevant when you add the fact that while it isnt uncommon in fantasy to have a protagonist of unknown heritage, it is definitely one of StarWars original twists was that the villain was the protagonists father.