I always found Jedi to be the weakest of the original trilogy. I'd rather watch it than Empire Strikes Back, but Empire was a better movie. The acting, especially the supporting roles and Carrie Fisher, just wasn't that interesting. The Ewoks, for such important characters, were a real problem. Even with the size and cuteness issues, they could have been more developed if they could speak. Chub-chub just wasn't enough expression. I didn't have a problem with Luke being confident. A Jedi should always seem confident. Luke went far past confident into cocky, and for that he had no justification - perhaps other than ignorance. I liked the space battle, but the Falcon should have had more trouble than the TIEs in the interior. Still, that was exciting.
Sith was a good movie, but it had the problems of the bad guys won in the end and Christiansen not being a good enough actor to pull off the role in which he was cast. I can't blame him for that failing, but I do blame whoever cast him as Anakin. Obi-wan was a great character and it was sad to see the younger version go. I can get technical and justify the later version not seeming to know R2 and 3Pio, but I won't. I liked the pace, I liked the final battle. This movie made a great lego game!
Sith, for all its flaws, was a good movie. Sure, it will never be considered a great movie by any critical standards, but I enjoyed it. Some parts of it were just really stupid. Jedi, for all its flaws was about in the same situation. I can't really say there were some parts of it that were really stupid. I voted for it.