I realize that a proof-of-concept could range from simple to mindbogglingly complex, but could there be at some point in the future a game template for a turn-based 4x strategy game? You have RTS on the list, and that might do for most people, but I can’t stand RTS games, they don’t give me enough time to think about all the stuff going on. Just a personal observation.
In any event, an “end turn” button is kind of a big deal in a strategy game, whether it’s cooperative (a la dungeon defenders) or competitive (a la chess) or both (a la Emperor of the Fading Suns). Hopefully I just blew your mind with that callback to ye goode olde dayse.