[john70t]

I've been interested in the (at least partial) berm-house design for a while, but the potential drawbacks to this design are:
1)surface water drainage,
2)foundation breathing to prevent radon buildup,
3)interior air flow-through.

The south side will have the most light, so it's the best location for common/guest areas such as the common room, kitchen, and one guest bedroom. All require a view.
The north side is the best location for the evening-activities rooms like the bedroom, bath, and office(which can be swapped with the guest bedroom depending on day/night usage).

Air
-Plan around a "flow-though"air zone through the common areas and especially the kitchen. It's so nice during the spring and fall when flowers are blooming. -Shade the upwind source so the incoming air is cooler.
-A round-er building lets air flow around it and doesn't build up tree trash/dirt in the down-wind eddies. After sweeping the same place every day you'll appreciate this.
-Plant evergreen windbreaks so no walls/windows are beaten with cold wind.

Heat
-Have a long overhang on the roof(ala:Frank Lloyd Wright/Japanese). This blocks the summer sun from the interior and drops roof water further from the foundation.
-Insulate the bedroom walls/ceiling and create a seperate heat zone with supplemental radiant heat.
-A "perfect" roof using available material would be metal over 1inch plywood with 2x14 rafters and 14inches of sprayed soy foam insulation with fire retardent. Someday, consumers will have the choice of super-insulation such as "areogel".

The biggest problem/challenge to any home design is the ying/yang thing. Women tend to like more light, and an open-interior style so they can keep an eye on everything, and men often want the interior broken up into privacy areas.
Having a combination of these goes a long way in keeping relationships together and making the house more attractive for guests and re-sale.