Wooahh. You.. are from the future? Is it 3D?
But in seriousness, an "overhaul", or a rewrite rather, would probably take like 2000-3000 man hours, plus testing and all that. Cool? Yes. Likely? Not any time soon.
I know it would take alot of time but it would also lead to a much better Program. Though it is a Pipe Dream, But I would like to see Zquest have more I want to be able to at Least Remake Zelda 3 and Zelda 2 We got Zelda 1 down lets get the other 2 lol!