To the extent that the prequels didn't meet the expectations of many dedicated fans, I think GL was trying to wear too many hats.
He was trying to serve as the next Rodenberry/Asimov/Stan Lee.
He was trying to serve as the driving force in FX developement.
He was trying to serve as the one to pick up the Walt Disney mantel.
He has been astoundingly successful in each of those fields individually.
Taken together, inconsistencies were created.