Non-mumble-required lobbies should be their own thing that doesn't interfere with people that want to play mumble-required lobbies. Right now, if I want to create a lobby for a given map, I have to wait for various non-mumble-required lobbies to start before I can begin playing.
I'd like to suggest that non-mumble-required lobbies be ignored when creating new mumble-required lobbies so that lobbies with some resemblance of competition can be available at any time.