yeah, that's pretty cool. great work and good ideas.
one point though to say - not against - but as an argument for me why I actually not try such stuff: I'm more in waiting until one can build with logs as one could do more realistic, or, I let it be lol. Positioning the logs is actually a big problem, and for walls it's nearly impossible. But walls out of wood and perhaps ladders or stairs out of stone (with room underneath lol) are essential if building, or 'building' is absolutely not what it should be. I've builded many houses in SecondLife (and run an OpenSim-Server too) and I do NOT expect this here to be such comfortable than building there, but a bit more realistic than actually possible I do.
But again: This is no critic, great work, and I tried a bit with building walls too