Finally beat the last level. I wish I had some good hints, but I don't. That run wasn't even my best time, but the baddies must have been slow that round. So my hint: Try to shave your ride down to around 68-69 seconds and just don't screw up... If you can keep your boost going through the climb in the middle that does help a lot. If you are not in the lead at the bottom of the climb in the middle just hit the restart button, the enemies are faster the second half of the map.
Interesting concept, but the end end is way anti climatic (you loose because you do too well?!?). That game where fish eat each other is a cooler version of this concept of big eats small.