Thanks guys! I was leaning pretty heavily towards the Prometheus domes on Mars, but also considered blending in some Hadley's type structures, and given the Nostromo's refinery structure's similarity to Sevastopol, and how commonly such structures in the real world share structural similarities, similar towers might be in place. Also, given it's probably something of a hub, there'd be landing ports/docks, so I'm sort of thinking I might run with a bit of a mash. Don't be surprised if it looks a little Neo-Tokyo meets Silent Running.