Wow, we've had a similar idea for a game, but ultimately didn't thought about it far enough! Crafting longer and longer road definetly feels rewarding, and avoiding enemies quite interesting. Cool game! This concept has a lot of potential, if given a lot of polish.
The ui feels a little bit wonky, but it's functional. x3 speedup is a must, I think I would prefer even more speed.
Did you consider not destroying the roads the player already made in previous round? Was kinda expecting that aha