He wasn't the one, you invented that story, really, well part of it, but most ideas he contributed were the bad ones. New trilogy is more of his. Like was his contribution to Indiana Jones meets UFO crystal new age skull.
Yes, I am being way too sarcastic, but thing is he really is special effect guy and owns rights for Star Wars, not a great storyteller or actually artist loving the mythology. It's business to him.
I never believed he would make whole saga. Future of Star Wars universe is already sold for books and computer games. He would counter lot of ideas, and maybe his business consultants have told him making more movies woudn't bring enough money. And yeh, maybe he would like people to love his movies too.
I think it's also the age, old men tend to do some things differently.
Remains me of Michael Moorcock, guy who wrote Elric and other Champion Eternal stories. They used to be dark, cynical and good books. Then he took lik 29 year pause and wrote some additional Elric stories. Edge was gone, books were some watered hallf-assed romantic crap. Well, at least if you were expecting similar thing than younger version of him wrote.
This kinda change is rampart in literature. I know pretty many writers whose stories were great... but not the newer stuff. Musicians too. Some can hold to the spark of creativity but others loose it. Or go soft.