A haunted cemetery. Sounds weird, but with subways under the playfield transporting balls from crypt to crypt, tombstone standup targets, well used lighting, it could work. Some modes could be ghost hunting multiball, digging graves by shooting scoops, holes and saucers, zombie elimination etc. Everything could be lighthearted to balance out a dark and morbid theme. There could be a mode where you are a Cop who has to kick out some kids who are drinking on the property. Strange thing is that I can picture these things in my head, and how the layout and graphics would be.