Really interesting concept!
It felt like it was a bit too challenging in its current form though. It's very difficult to know which stations may need more bikes or have too many, so I would end up letting a problem build until it ended my run without knowing what happened. The most obvious solution (to me at least) would be to have some kind of hud telling players which stations have too many/few bikes, but that could also go too far and take all the challenge out of the game.