But only he really truly knows where the story needs to go.
#2: In absence of that script, the backstory for the film is far more interesting than the film itself. The battle of Jakku, the formation of the new jedi order, Luke training Han and Leia’s kid. That kid falling to the dark side etc. It’s an amateur writers mistake to not tell the most interesting part of your story.
I agree the backstory sounds more interesting than the film itself but a proper sequel to ROTJ would have been made decades ago and not now. You can’t really blame TFA for the 30 year time gap between it and ROTJ.