I found this game to be a lot of fun and well-polished too! Driving around was difficult but rewarding, and the concept was simple but also satisfying and enjoyable enough to keep coming back to.
I'd say at most there could be more hazards over time to make the game even harder, but I don't think this takes too much away from my enjoyment of the game, and I do think the controls along with the timer already adds a good amount of challenge and needed focus from me which makes the game engaging.