Another map might be interesting.
Like one with multiple spawn points, to eliminate spawn trapping.
Maybe one of the Freespace maps? Freespace 6 is fairly well-rounded. Lots of space to build, plus it still has water for people who want to make boats, the town for people who want to fake a roleplay (which I've seen a bit of, like a guy who made a restaurant and opened a drive-up window. Good times.), plus you can play a cool game by sticking someone up on the spire of the building frame and shooting them with a Jeep from the ledge of the aerial roads into some dumpsters for points.
I think at least having the option of voting for a different map might be a good thing, then throwing a solid set of building maps on. Maybe even a couple of gamemode maps, for some variety.
Or not, either way.