Here's some info on rammed earth floors - click here
I'd love to combine the rocket stove mass heater into the rammed earth floor, whereby the floor itself becomes the thermal mass.
Now the green roof while truly AWESOME in terms of insulation, creating habitat, and longevity may need to be sacrificed in the interest of speed of construction and water harvesting yields. So how about something like this? then build my cob walls and polycarbonate sheet the south facing side.
If I was a rich man - I'd just get this, and just insulate it very well.