Thanks for the reply Guarren. I really like the arched doorway idea, definitely something I'd be into (and I've added it to my list of options

). I agree with the corner windows, I was looking to do a good number of windows, so cornering them makes sense.
As for putting it on wheels, that was definitely one of my thoughts as well! I love the idea of traveling around with a comfy house, but I don't have a vehicle to do that with at present. I'll settle for a stationary one for now, and use it to give me ideas for a mobile one should I ever get to go that route.
On a side note, the location for my small house might be built into the side of a hill, so that could be interesting. I'll have to look up grass-roof houses for some more input on structure and whatnot, but I like the idea of having more easily regulated temperature.