Some of the last details I added to our scene that I think helped bring it to another level were the headlights and tail lights on the car. The tail lights were part of the fill layer and the headlights were on their own layer so we could have more control over them in post. We also have a layer in Shot 3 where the headlights from the car on the right is shining onto the car on the left.
I looked at a lot of reference to see what these lights look, especially in darker lighting. The headlights have two main parts to them, an outer ring around the whole headlight glows as if a bright reflector, and then the actual light bulb inside. I used the geometry of the car and turned it into a mesh light for the out part, and then used a point light for the bulb. I don't want the headlights to get blown out, so I was careful in how bright they got. Below are some of the main references I used to create them.
The red tail lights were a little more difficult. In real life, the actual lights aren't red, but the red plastic reflectors that it is shining through is what is making it red. So I kept this in mind when making the lights and tried to recreate this. I also wanted to make sure that the tail lights didn't look too much like brake lights because that wouldn't make sense when it is driving down the road, so I wanted to avoid that. I tried to balance the brightness, and then allow there to be a little bit of glow effect in the compositing. Below are the images I used for reference.
These two images are what the headlights and tail lights look like in our shots. I think the headlights could be toned down a little bit because they are getting a little bit too blown out. Another thing we need to add to the scene is the headlights shining on the ground.