I'd be inclined to say that Star Wars trilogy was a success because it as the right place at the right time. The prequels have some good concepts with some faults which I personally forgive, but it seems the general public doesn't.
The elements are there to have Ep3 go all out. Between the falling out of Obi-Wan and Anakin, the birth of Luke and Leia, Palpatine being a more sneaky bastard, the general chaos that most likely will happen, Ep3 may pull it off. I'd personally would like to see a young Han Solo, but that's doubtful since I'm guessing he's 5 years older than Luke(Most likely Luke and Leia will be babies in this one). The people didn't like Lil' Anakin, so no Lil' Solo. Which probably means no Chewbacca. Damn...