The movies were tinkered with vastly before they were even released, as we saw in Deleted Magic. Episode IV is not the movie Lucas shot, but rather what came out of the editing room after a serious re-evaluation of what he wanted out of the film. I think it's a shame that Lucas didn't save Episode I in post the way he did with Episode IV, but looking back at what Episode IV came out of, I think there's plenty of hope for the prequels. I already enjoy them even though I consider Episode I to be inferior to the originals, with Episode II being somewhere between that an Revenge of the Sith (which I hold to be of similar quality to the OT), but I think that with a bit of re-tooling they could be pretty darned close to where the original trilogy was at.