Extreme Cold Weather Camping

My Bigfoot camper which I've named Sasquatch, is generally considered the best rated winter camper on the market.  While my model is not longer available, that hasn't changed.  Some other brands like Arctic Fox, and Northern Lite, are perhaps as good.  None are better.  I've read that this is the camper used by the Royal Canadian Mounted Police, to patrol above the Arctic Circle in the winter.  My brief period of ownership in cold weather has validated this.

My camper has R12 insulation with 1.5" of Styrofoam insulation in the ceiling walls and floor.  It also has double pane thermal windows on all the windows except the bathroom.  It came with thermal blankets for the skylight vents and door glass--the Velcro has aged and needs to be replaced. 

I can see a few areas where I can improve the insulation. I'd like to add insulation on many of the access doors.  The charging cord is a pull out type.  I may replace that with an sealed connector and external cord.  I would lose some interior storage while eliminating a potential cold spot.  Also, I can add flexible foam insulation to the overhead vents before covering them with the thermal blankets. Some people use bubble wrap to windows, which lets in diffused light and adds R1 insulation to the windows. I like the idea of diffused light for more privacy, but I'm not sure I need more window insulation.

I tested my furnace in 9 degree weather recently, and it brought the camper up to a comfortable temperature in 15-20 minutes.  In 30 minutes I was not chilled at all.  After an hour it was well over 70 degrees and I was peeling off layers and turning the thermostat down. 

Thermometers:  I ordered a wireless thermometer with four sensors.  One inside and three remotes.  I plan to put one outside, two in the basement to monitor the temperature in the basement, which will allow me to reduce inside temperatures and conserve propane while I'm sleeping, and still protect my tanks from freezing.

Some people install catalytic heaters.  These don't require any electricity but the put off water vapor.  These don't heat the holding tanks unless vents are cut with push and pull fans to circulate the warm air.  That seems like a lot of work to accomplish something the existing furnace does already, without putting water vapor into the air.  I would like a second more efficient heat source that does not require electricity, but I don't want to add weight or complexity.  For now I will defer this idea as unimportant in the like-to-have-but-not-necessary-category.

In any event, over the next year I will be looking at ways to improve the already great insulation of this camper.