I was thinking of starting my own cache with a travel bug and making it an aviation theme. I was looking around to see if anyone else had that idea and found your posting. I wish you well.
My goal is to be a bit different. I would like my travel bug to fly on any aircraft (commercial, general aviation, experimental, military, you get the idea) and log the aircraft and the origin and termination of the flight.
We'll see how it goes.
Good luck with yours.