Man, that does sound like a great idea. I would love to see that. There are already some good thoughts posted here, so let me just add:
Initially, I hated the movie Faramir. The first time I saw RotK in theatres, I thought it made him out to be a bad guy. The EE helped a lot, yet he still seemed to have weak character, and that's what I didn't like. Yet the part that still bothers me the most is that meaningless trek to Osgiliath. If you take that out, you could get both
Estel's idea and
Imladris's flash-forward in with plenty of room to spare. I don't know, maybe those ideas wouldn't have worked (I don't see why!) but I just wish we could take Osgiliath out of the picture!
Oh, and I wouldn't mind not seeing that brutal scene with Gollum again. The one where Faramir watches two of his men beat Smeagol. And then that bizarre exchange of words between them, well, actually I thought that was kinda *cough* funny, but, ehem.
But the beating made Faramir look cruel and really made me not like him.