Not sure if this is even in a genre you're a fan of but I've been really into Rogue Legacy lately. its $15, has randomized room layouts, Rogue-Like elements to it, it can be pretty tough and it would probably last you awhile. Highly suggest you use a controller with it though, haven't tried KB controls myself but I've heard they're not so great
Thanks for the suggestion. I actually already spent the $20 getting World in Conflict and Battlefront 2. Unfortunately World in Conflict is giving me an error any time I try to run it "Failed to start game (app already running)."