To the experts, How would you insulate the following?

40'x48' Post Frame Building. Steel Siding. Reflective Insulation with White Scrim Finish. 16' interior elevation to bottom of trusses.

As we all know, that 'Reflective Insulation' is really an R-0.5 at best.

We are currently living in our RV inside this building (Our Shop) while we work the land, prep the build site and build our home.

This winter has been a light one from what we've heard and we have been grateful for that as we get things going. That said, the wood stove can only do so much keeping the temp above 40 degrees. Some days I can actually get the temp up to the mid 50's, but every morning it's back down to 40 or less.

The original plan was to spray foam the interior 1"+ and then Fiberglass on top of that. However, I've learned that I would really need 2"+ of spray foam just to keep the condensation under control with the 2 different types of insulation. With the cost of spray foam, I just can't justify spending that much money on 'Our Shop' when I'd rather spend it on the house.

I'm wondering if I can safely use spray foam around all the doors, windows and any exterior penetrations (electrical, plumbing, etc.), and then use Fiberglass (R-15min) on the inside framing. The ceiling getting an R-38. The use of the spray foam being to help seal the building.

I'm not looking to have this in any magazine as an energy efficient shop, just something I can throw some wood in the stove and be comfortable in while using it. I'd like to believe this plan of attack will allow me to do just that but do I need to worry about moisture issues doing it this way? It does have a ridge vent and is open to the shop currently. I would build/put in a ceiling roughly 2' down from the peak so we can keep the truss look. Future plans call for dry walling the complete interior.

FYI, the area around the windows and pictured door is having an enclosed office (with bathroom) built around it that will have a mini split system installed to keep that section comfortable. It will be fully insulated to the shop. I also have two large insulated roll up doors going into the shop.