I should start but saying I know very little about this subject area. I stumbled across some amazing videos (so please forgive if this is a topic that has been covered elsewhere!).
I've seen the videos with on board cameras. How about taking it a stage further whereby remote users could control cars, trains and boats that are on a fixed path. So the user can only move forwards left and right. This could prove a lucrative additional revenue stream during the overnight period (the vehicles would need to have miniature, live streaming stabilised cameras that would be unsightly for daytime visitors). During the evening, the other side of the world can log in and control numerous vehicles. (I have several potential games in mind and a strategy that reduce hardware/software costs to a nominal amount. ).
I would be very interested to know if something like this has been considered (any assessments or testing ?)