I'm not sure if its been done before (or if its do-able with the lighting) but maybe using the central structure on impact as the center of the map and building a circular structure all around it from there. That way, you could have a two-floored structure with a pre-built center figure that would be rather aesthetically pleasing. It could even be a little bit like "Condemned" from Halo: Reach. Anyways, I hope this helps!