I like the idea of aircrete (or foamcrete) construction and geothermal. There's basically no reason to spend hundreds of dollars per month to cool a home, but our darn stupid constriction paradigm requires it.
What we know of today as modern construction is a more permanent version of settler cabins, made to be less temporary and (slightly) lower cost construction.
Stone and earth construction regulate temperatures much better, and working with the natural thermal patterns of the earth rather than against them costs a lot less energy.