Cappa, Stock CTF maps only. I don't like Well, and the Sawmill one is too much of a FPS killer, so we are stuck with 2Fort and Turbine for now. It is regrettable that Valve has done a piss poor (Actually there isn't a strong enough negative adjective to describe it) job of supporting the CTF mode with decent maps. I'd love to see a few FPS friendly, simple CTF maps come out.

Custom maps kill the server, so that is not a good option. The most popular TF2 servers on the net are 24/7 2fort. I only added Turbine because people were bitching that they were bored with 2Fort.