There should be much colour in the game and here's the proof. Colour is good for the eyesight, if you don't see enough of a certain colour, your eyes are un-used to it, and you might go epileptic or somethin. The more used one are of staring at a colour, the more it feels non vital and doesn't surprise you etc. All in all it enhances your brains abillity to see colour, to actually see them. Without colour you might not live as long.