George is a visionary genius.
Creative characters, creative worlds, concepts, stories, etc. Beautifully shot sequences and set locations. George was that cat.
People like that don't come along every day.
His flaw was dialogue. And sometimes fleshing out his great ideas on screen. And George the businessman with merchandising got ahead of George the writer when it came to his stories at times.
All in all, George was a good dude. He grew bitter from some of the critique of his prequels. This was his baby, so he took it to heart. He was old and it was time to cash out. He had enough.
I think that is why JJ played it so safe with TFA and ROS. If George wasn't safe, then nobody is safe if you don't come correct. JJ didn't take any chances, and was just going to placate the fanbase with rehashes. Rian Johnson was oblivious to this, and he got that work for TLJ.
George,a creative talent, gave the keys to a non-creative, executive in Kathleen Kennedy. That wasn't going to work. Business and creative sensibilities are often like oil and water.
Kathleen Kennedy is all business. She thinks like a major studio executive, and it shows. Knows nothing about creativity. That is why the new Trilogy is all over the place.
Rogue One was fire though.