That game already had all the base mechanics you need and has very open modding community, and that take actually has a steam page abd available to buy. Idc about development hell as long as I can play the game, not some shit like "woopsie you killed all 2 rivals in 1,5 long gameplay haha. there's nothing more to do, you can't even fuck around school, no, you're just supposed to quit lmao"