Harrison has tended to treat Han Solo the way Shatner used to look at Trek and his involvement in that franchise. I know Han isn't the deepest, meatiest and most three-dimensional character for an actor to tackle, but it made him a superstar and launched his movie career. Running from him is just silly.
I'm sure he gets just as much if not more attention for playing Indiana Jones after all these years, so he should just embrace Han Solo for what he was/is and be happy for the gigantic boost that the role gave his career at a very fortuitous moment in Hollywood history. He was never meant to be the most textured and challenging role in the Original Trilogy because the main focus was on Mark Hamill and Darth Vader and the films were supposed to be about the Skywalkers, not Han. I hope his involvement in Episode VII makes him at least a little more open to discussing the films and not acting as though they're some embarrassing skin flick he did back in school.