Dark Vision (easy implementation)

What Feature would you like to see included within TaleSpire?
I saw someone request Dark Vision, but I thought the suggested implementation for it was kind of silly and nonsensical. Instead, I think it would be pretty cool to add a GM toggle for characters with Dark Vision (just like you have with "knockdown" now or the torch). When toggled on, this wouldn't add a special effect to them or something (as suggested previously). Instead, it would simply take whatever light level the GM has for the area (the atmospheric light level), and add a sliding scale of light to what they actually see on their screen. Just like in real life, only that character is seeing things that way. And I say a sliding scale, because if the place is very bright then Dark Vision isn't a factor, and you wouldn't want the screen to look even more blown out for characters. You could have a maximum (like 1.0 exposure) that Dark Vision helps with, and increase that amount as the exposure reaches closer and closer to 0.

Anyways, I thought this would be a lot simpler to add (code-wise, just some simple math) than a magical effect. You could have some kind of GM indicator for it (that it's on), of course, but it doesn't have to be fancy.

What situations would this Feature be useful?
This would help greatly with immersion into the atmosphere. Those without dark vision will have to "light torches" or "cast 'light' on a pebble" or something. They'll have more realistic disadvantages/advantages in these circumstanes.

Additional Thoughts/Details

You folks are doing a bang-up job! Thanks for all the hard work. The program is excellent!