I mostly use the flashlight mode to see objects that are in total darkness. A new lighting system must be developed right after the release of planet grids, so that dark objects can still be seen at distances where some visible light from nearby stars or galaxy clusters exist. A new system to deal with different light sources would be required. Light is also visible in different colors and luminosity strengths and wavelengths.
For example, when placing a hot rocky planet fairly near another object, such as an orbiting gas giant or rocky planet or moon, the red hot glow should light up the dark side of the other object. If the hot object turns yellow, white or blue hot, than the intensity of light reflecting on the other object where it is dark should increase in luminosity and become brighter, therefore change in color due to the light and heat intensity.
Another example would be, how would the dark side of the Moon appear like if I place a red hot Earth orbiting near it. What about making a blue hot Earth with its Moon orbiting it. How much light and visibility would the dark side of the Moon look like.