I just HAD to revisit this...
This experiment has serious merit!! 👍👍
I've been doing strengthening exercises, by removing Paper and fitting Poster Board (re-laminating with White Gorilla Glue).
As expected, a net weight GAIN was the result!! 😳 Not terribly tragic though.
Because of my physical limitations, strength is more important than weight, within reason of course...
Your fit and finish skills are far superior to anything I'm now capable of with my Arthritic Gorilla Hands! However, if I can EVER afford a stock of 1/32" Balsa, I WILL be experimenting with some of your theories from this thread.
BTW, have you ever experimented with using Parchment Paper as a laminate? Except for the lack of being able to make smooth compound curves, I hear great things about it. More resilient than Paper, waterproof, and decent tensile strength...