Oh super interesting concept I love the idea behind creating your own "obstacles" It felt like real traffic at times since all the movement became natural without ai. Really clever!
That said I would have maybe made the map a little smaller so it gets chaotic more quickly. Especially in a jam you want to get to the juicy stuff as quickly as possible.
I appreciate the sound but it did become a little repetitive since it was quite droning. Maybe some slight variation between the cars or some music to along with it?
The arrow is a nice unobtrusive way of indicating direction but can be a little misleading since I guess it is always pointing straight at it?