Bingowings, that new crawl is simply amazing! Great job man, as usual.
I don't know if we could actually make that plot work with the material we have, but I think it's an interesting take. I agree that we never truly saw the Golden Age of the Republic, but I don't think that would have been possible with the prequels. If Lucas wanted to show the Golden Age of the Republic, he would have had to go back in the Star Wars timeline for possibly of years, and had he done that, the prequels could not have been about the fall of Anakin Skywalker and the rise of the Empire.
I think Lucas handled it quite well, the Republic was already falling apart when the prequels start, but the main characters know it too: Palpatine says as much in TPM, and his words are proven true in the Senate scenes, in AOTC, Sio Bibble mentions how powerless the Senate is, and Dooku (in a deleted scene) says that it's time to start over. And we have characters who are fighting against it, like Padme and Dooku, albeit for differing reasons.
What might work for a scenario Bingowings is talking about, is putting more emphasis on the characters who are fighting to keep the Republic together, like Padme. The deleted scenes from ROTS with the start of the Rebellion would work nicely in this. It would also create a nice bridge between the PT and OT: Leia follows in her mother's footsteps, kind of like Luke follows in his father's. It also works nicely as a mirror: the childeren succeed in where their parents failed.
I also wanted to say that I think not having Anakin confess the Tusken slaughter to Padme is a great idea. (don't know who said it, but props to you!) I've been thinking about the same thing. It could make the scene in the garage where Anakin breaks down the turning point in their relationship: Padme sees this broken man, and she wants to care for him. Also, it could also give the scene where Obi-Wan tells Padme about the slaughter of the younglings in the Temple a lot more impact. Here, Padme could realize that Anakin killed the Tuskens too, and the line "Not Anakin, he couldn't", gets a whole new meaning, because she knows Obi-Wan is telling the truth, but she can't, or doesn't want to, accept it.