I think it would be nice to have a couple of color options for the red dot sight to choose from in the options menu. I don't know if it really affects anyone else, but I sometimes have trouble discerning the red dot and end up aiming for "the middle of the sight", where I would have less trouble if it were, for example, green. Not sure how complex of an addition this would be, but I feel this little change could make a huge difference to some people.
-
I believe higher lvl weapons especially ones with names will have special sights like a gun called blue blazer might have a blue sight to go with the theme