Color Banding and Noise
Color banding is that effect you get with gradients when there just aren't enough bits to represent all the colors in the gradient. Check out the Google Image Search for color banding to see some examples. In the low light areas of EDM, there are only so many shades of grey and so what is supposed to look like a smooth transition from light to dark ends up looking like several quantized steps down in brightness:
Today I tried a little tweak in my shader that simply introduces some noise to the lighting texture before it's rendered over top of the scene and it appears to really do the trick!
There is a trade-off however, because just washing out the light with graininess does add a sort of grit to the screen that might not be desirable. Right now I'm liking the new aesthetic so I'm leaving it as is for now (after a tweak I just made so that the noise does not reduce the average pixel brightness as it does in the above screen captures). I'm constantly having to revisit lighting so this won't be the last change, but I'm really happy with the way it's looking right now!
If you're looking at the above images and saying "dude you're crazy they are not visibly different" then that may be due to your screen's brightness or gamma, or may be I'm just really trained to see it because of how exaggerated it looks when the game is in motion (seriously it looked mega bad when two coloured lights "merge").