Alright, I've got to admit; I need some inspiration. I'm making a territory control map, but I can't come up with a theme. All outdoors? Indoors? Desert? Plains? City? Anyways, I just wanted to get some opinions from the community. So far, I'm thinking a city, but I'm not certain yet.
Don’t worry about the theme of your TC map right now. When you’re done with the layout then start thinking about the theme. Layout for tc is far more important as tc maps are notoriously hard to make and balance that only a few people like Schmitz and YM have managed to get their tc maps past a1 and into beta (Meridian and Strata respectively).
Well, there's a problem with that. If I do a desert theme, that'll have to be a different layout from... say... a city. I know Mossrock exists, but that's different. Think how despite both being 2 cap, 3 stage, Dustbowl and Egypt are very different.
If you have no particular theme in mind, then you're probably best off trying to do some design work first and see if that springs any ideas to mind. You may also want to consider what the gamemode might benefit from in terms of thematic elements - Hydro certainly benefits from having a theme that allows for giant rock walls to divide each territory from one another. You'd also be surprised how much theme-agnostic geometry you can create. If you make all of your buildings vaguely industrial, its easy to convert between themes. Theme mostly helps solidify geological forms and specific landmark buildings. The hydroelectric plant and spillway are very specific to Hydro's theme, but the dish and other point are relatively easy to transplant into other themes.