Another advantage of 3d printed homes would be the wide selection of designs available. Only imagination and local planning commissions would limit the possibilities.
A couple of decades ago the talk was of living in Yerts.
I like the idea of excavating a hillside, building into the space, with light tubes for nautral lighting, then back filling over the structure leaving a Southwestern exposure out of the hillside. A person only needs a bathroom, one or two bed rooms, a common lounging space, a dining area and food prep area, with a utility room for HVAC and food storage.