It's been done to DEATH! Might be worth doing again though if we can add something new to it. Thanks for the suggestion though, EL.
Here are a few ideas I've been kicking around:
1. A bank building where the obstacle is to "crack the safe" while dealing with the guards, security guns, etc.
2. A subterranean cavern crawl with zipping mine carts and lava and falling boulders and fun stuff!