Lucas being a stubborn, detail-obsessed filmmaker also led to American Graffiti, Episode IV: A New Hope
and - as producer - Raiders of the Lost Ark.
Being a stubborn sunnuvabitch isn't necessarily a bad thing. If they're capable of producing terrific screen product I say let them be stubborn. It never hurts to encourage advice and a more open and democratic atmosphere on a set but it's not a guarantee that the finished product will be any better.
The first Flintstones
film with John Goodman had dozens of writers and input and participation across the board and look what all that democracy and diversity of opinion got us.