The Jedi played by Samuel T. Jackson for example is just a prop. Even Jar Jar Binks has more going for him than poor Jackson's character. Natalie Portman's character is unknown also. She is Luke and Leia's mom; other than that she has no soul.
Don' get me wrong, I like the films. But as I said before, simply putting the actors and characters before the special effects would have made a world of difference. This is not hard. It just requires a real film director.
Saying Star Wars II is a kids film and we grew up is a cop out. "Babe" is a kids film with real characters (human and animal), that adults can all identify with and love. It can be done.