Screen tint - a way of creating atmosphere in game

There've been talked about atmosphere, in the game, and what i thougt about, when hearing about atmosphere i wasnt thinking of new items, i was thinking of "better graphics."

And then i got the idea of screen tint. Whenever you enter a biome, the screen tint will change. You will fx. in the birch wood forest, get more colory colors. Its more light, maybe a little bit of yellow tint, beacuse of the sunshine. But then in the dark oak forest (which should have a darkgrey sky) you will get more a more darker tint. (Well basically the tint would be the same as having tinted glass that instantly goes in front of your character's head, just a little more transparent.) This should maybe also be togglable.