My favorite real time strategy game these days is Offworld Trading Company. This is an economics-based battle with no armies and not a single shot fired. Instead, you wage battle for dominance of the economy on a martian colony.
http://store.steampowered.com/app/271240/Offworld_Trading_Company/
The game is simple to understand but as deep as you want to get. There is a commodities market in constant flux, opportunities to sabotage your competitors or grant yourself a boost from the black market, and infinitely different strategies you can employ to be successful. I've played quite a bit and only just scratched the surface. You can see a recent game I played here:
If you're interested, please feel free to ask me any questions you have. You can join my streaming chat channel here.