Love the layouts and how the tracks look. Two small issues: Firstly, during replays, there is a odd rectangle just above the horizon that follows your car as you drive. Secondly, after overshooting the first chicane on the oval track, I discovered that the ambulance has no substance and I just shot straight through it! Maybe a solid object (like a small fence or tyre wall) might be a good addition to these areas of the track - maybe they're not there in real life, but I believe they would add to the experience.
Looking forward to future updates.