Yeah, if we have to contend with mountains any plans made for a flat area will be useless. We'll build a communal building or two when we get there and plan from there. Once we see what we've got, we can plan on the forums what to do with it.
Also, I'm desperately curious to know who did this:
(And how on Earth they managed it - that castle is, I think, every bit as isolated-on-a-tiny-island-in-the-middle-of-a-lava-sea-without-overhangs-or-bridges as it looks.)