I disagree that Ep 1 was the only legitimate "bad" one. They all shared the same problem: the director. Lucas can't direct. He learned that lesson after Ep 4 back in '77, and went to other directors for 5 (clearly still the champ) and 6. Why on Earth he thought he could re-take the director's seat and make 3 good movies is beyond me. He failed.
It wasn't Christensen's fault, or any of the other actors on set. Each (including him) are decent actors in their own right assuming they have good direction! And they didn't.
IMHO anyway, Lucas should have stayed as the writer, producer, and techie adviser of the 3 films but had someone else with more chops handle the directing. I'll bet a paycheck (and they're sizable.. ;-)) that we'd have had much better movies with nothing else changed. Including Jar-Jar.
jas