Awesome, thanks for beating it! Yeah it's really chaotic and easy to pull you back from 1st position. They speed up if you're ahead and slow down if you're behind, but it's not necessarily easy to overtake them with all that's going on. It definitely needed a few nerfs for a game jam.
I never tried to jump over the hills, but I have it set up so you always have a target waypoint along the track. You can skip the target waypoint but only as far as the next target waypoint. It works in a way so you can have shortcuts in but not skip the entire thing. Good try though xD