Unfinished projects subconsciously wear on me. If you can financially afford whatever else is needed, it would feel good to get it done.

I would go electric if you are already setup for it and plan on actually flying the plane. If you want to stick to the roots you could always use a huge Nicad or something In seriousness, it would be nice to have it 'appropriately powered' if you plan on flying it. So I wouldn't go overboard with the batteries/motor, I'd try to make it fly like an adequately powered classic plane.