And I can just see you sitting in the cockpit of a 24 foot lil' Satan....

Interesting thought. The question is just how much of a difference WOULD there be? The material may well be lighter but what about modern vs classic covering and how much dope is needed? What about the engine? Use the original at the original weight or something modern that makes the same power with less weight?

People are still the same weight and with two on board that's a very significant portion of the AUW.

So off the top of my head we sure are not looking at a HUGE loss of weight. In fact the actual framing gains may only account for perhaps a 15 to 20% reduction overall in the gross loaded weight. At that point it would provide a nice shortening of the takeoff and a little better climb rate (which was somewhat glacial with two on board on a hot day). Or it could also provide for a little more useable cargo weight if flown at the same AUW.