Do you realize how insanely easy Keno would be to code?

All you have to do is decide on a payoffs table. You could even do promotional periods where the payoffs are loosened, or even payout in favor of the players! (Think about this one when you're trying to drum up customers!)

Also, it can be a global game, and it can be a bonus for casino owners... follow me for a minute...
Keno takes up a lot of real estate on a real casino floor, almost as much as a sports book (except for multi-game machine Keno, which doesn't count). A Keno board in a casino could be designed so that it, along with the required seating, takes up about 1/4 of a floor, and so that a casino already has to be a certain level to install it. (Maybe allow another variety that can be installed in a level 1 casino, but the owner has to be a level 20 or something.) If you'd like to get really fancy, make it so that the Keno results show up on the Keno board in the casinos, not just when you're on the game screen.