Ah ok, yeah with only one light source the raycast makes sense. I had tried before using a trigger to detect when the player is in range of lights, then calculate visibility by raycasting to the player and calculating how close the player is to the light versus the intensity of the light. Became too much of a pain so I just switched to using a render texture.
Yeah that's pretty much what I figured, since frankly I found no real reason to actually use the pause menu other than just to see if there was one.
Cool stuff.