I've thought about releasing just the tennis rules, without the restaurant aspect attached. I came up with the pun title first, and expanded out from there with the idea. The tennis rules are kind of a strategy-rpg mix, and there's rules for improving between sessions.
Until I do release the tennis rules separately, I do think you could easily separate them from the restaurant management section if you wanted to run a pure tennis game. It'd be almost like running a Street Fighter tabletop game, but tennis instead of fighting lol