It seemed fun at first, but not for long enough to get through it. The cars spawn at a good rate, but the patterns they can spawn in often result in the player having to make a choice between two direction before they find out whether either of the directions will turn out to have more cars forming a dead end. Also, after a few tries, the movement of the lane indicators starts to feel like flashing lights, which makes the cars harder to pay attention to.
This is minor, but when designing a game, I recommend choosing what types of controls you're going to have available early and then trying to be consistent about supporting them, that way your player never has to figure out more controls. In this case, your actual game uses keyboard controls, so the dialogue and menus should also be allowed to use keyboard controls. The mouse control is still good, since the player can use WASD thus making it intuitive for FPS players, but if the player finds the arrow keys first, then switching between them and the mouse will feel weird and they won't necessarily realize that WASD is also an option.