So I tested the game on the WebGL version.
Overall, I liked the environment graphics and they feel ok at this stage. The car models however are too simple, especially given the fact that the player's car is by definition the biggest thing we can see.
I see a lot of room for improvement gameplay-wise :
The biggest issue IMO is the car's behavior. It really doesn't feel like we are driving a car, it looks like you applied a (strong) rotation around Y axis every time the player tries to turn, and it bounces back when the key is released. Car physics are very tricky to get right and I don't think you need realistic physics, but this is way too far from a driving simulation.
For the speed feeling, it would probably beneficial to play with the camera's FOV depending on the speed. Also, when turning the camera should lag a bit compared to the car rotation (if the cars turns left, then the camera sees a bit of the left side of the car), right now it's just at a fixed position. A speedometer would be nice too.
Also, I tried the "combat" mode but did not understand at all what was to be done, clicking on the mouse seems to do nothing.
I think you have a lots of runtime errors, my browser's console was spitting many errors, you probably need to check thoose.
Good luck!