One great thing about something you build for yourself is that it is...well...for you.
My plan was to have an easily heated/ac'd area that was quiet...then I drove the FE skoolie
The idea is sound if you want a controlled cabin for 2 people traveling...a family would be different; esp. If only the driver was seperated from everyone else.
My thoughts were to enjoy the ride,then you can easily "seal off" the area that suffored from heat loss/gain and enjoy the mid and rear cabin areas.