It could be great to have neon lights on the outside of the bus that would light up with various strength levels when the passengers are really going fast on the pedals. When the group reaches a top power production level, a bolt sign on the side could get lit up.
Just a nice way to gamify the experience and it can even be used for competition when there are organized tours with multiple busses at the same time. Jeep safaris in exotic tourist locations compete with water fights when they pass each other. While this would be a resource-saving, rather than wasting competition.
I don't think it would take that much energy to power those lights so it would be worth it in terms of saving money on the marketing too.
Weekly leaderboard winners in terms of kilowatts per hour created could get a different tour for free.
Definitely should have the speakers sound a loud "Yabba dabba doo" from the Flintstones when a certain threshold of power creation is reached. :)