It's late, so just a brief response for now. I show a details where the floor deck is essentially 3/4" smaller than the skin. A 3/4" Ribbon band is added to the rim joist providing a solid nailer for hte bottom of the panels. Light switches should be near doors so the wiring runs up the jamb. Unfortunately the switch and outlet boxes penetrate the skin, you can design floor outlets or live like many of us in old houses do and just not have outlets in the exterior walls. Radiant floor heating is just one system that reduces the impact of heat delivery.

In summary there are a number of technologies and techniques that when properly planned and implemented can help one realize the dream of the "Learning House".

Hopefully we'll see some more contributions to this interesting topic.