I like some of your ideas for your shed. I just finished my grow room which is like a big cooler its so well insulated. I covered all the cracks and holes with spray foam, I love that shit. than I used fiberglass insulation, and after that 1inch thick Styro sheets you get at Home depot. That bubble wrap that is light reflective works very well and would be good for all the walls if your looking for the best insulation. Or just for the roof to keep heat signatures away as i used it for.