Really cool idea. I've often thought about creating games with physical objects controlled remotely (my idea was something like RC cars). I'll give this a shot.
We were thinking of using an RC car for part of this experience, but figured we'd leave that R&D project for another day.
Our main concern was designing/modifying the car (and its play space) in such a way where it doesn't get stuck. One of our goals was to make this an experience that can be managed and reset remotely by our team, so we wanted to avoid manual intervention as much as possible.
One way to get around the latency issue with RC cars is to pre-plot the path and build a puzzle around that. (Not that there has to be a puzzle in there.)
Also, if you like scale models, have we got somethin' cookin' for you!