Spence, this is an incredibly intriguing concept. I am very interested in this edit.

Without having checked out the 8 minute preview, I will say that if you can make a dubbing work, consistency would probably be good.

A few comments, though, in terms of the idea of being a throwback to the classics. I like the idea, but being a fan of classic films myself, it seems that some things, as is, might work against that feel.

The string quartet stuff is good music, but it tends to actually give more of a contemporary classical flavor feel to me. I would strongly recommend seeking out Golden Age film music, or late Romantic period concert music (because this was the style from which film music back then was most closely descended). I'd be glad to recommend some scores/pieces to consider if you'd like.

Also, I'm surprised that you find it difficult to get good black and white shots out of TPM--if anything, that should be the easiest to get better material that translates to that classic flavor. In the teaser trailer, particularly the AOTC shots of Anakin and Padme along with Anakin on the speeder reminded me of independent films far more than old school epics. Some of ROTS looked a bit better, but the shot of Palpatine definitely stood out.

Now, of course, this is your edit, and if the aesthetic you've got is what you want, that's all good, but if you do really want to go for the flavor of a classic epic, these things definitely come across the opposite. As is, the impression is more of a contemporary film in which the filmmaker chose to shoot in black-and-white.

Either way, it's a very interesting project, and I wish you good luck and productive editing!