In your Edelweiss house you use 2x6 studs. Why not use 2x4 studs and add 2" rigid on the inside?
...for this reason. The best is to drop the large windows and go for smaller openings, but the building site was just begging for that sweet forest view in our case, so with the view and solar gain in mind, we have no regrets. Great question to bring up, thanks!