Here are some pertinent responses from JJ in an interview he did. I liked the jab at Lucas in the first answer
==============================
So I tried to not forget the mistakes I’d made, but I also tried to focus on things that I find inspiring about cinema. I asked questions like “How do we make this movie delightful?” That was really the only requirement Larry and I imposed on each other: The movie needed to be delightful. It was not about explaining everything away, not about introducing a certain number of toys for a corporation, not about trying to appease anyone. This has only ever been about what gets us excited.
=================================
The script for VIII is written. I’m sure rewrites are going to be endless, like they always are. But what Larry and I did was set up certain key relationships, certain key questions, conflicts. And we knew where certain things were going. We had meetings with Rian and Ram Bergman, the producer of VIII. They were watching dailies when we were shooting our movie. We wanted them to be part of the process, to make the transition to their film as seamless as possible. I showed Rian an early cut of the movie, because I knew he was doing his rewrite and prepping. And as executive producer of VIII, I need that movie to be really good. Withholding serves no one and certainly not the fans. So we’ve been as transparent as possible.
Rian has asked for a couple of things here and there that he needs for his story. He is an incredibly accomplished filmmaker and an incredibly strong writer. So the story he told took what we were doing and went in the direction that he felt was best but that is very much in line with what we were thinking as well. But you’re right—that will be his movie; he’s going to do it in the way he sees fit. He’s neither asking for nor does he need me to oversee the process.