I have a couple of suggestion with the game key mapping. If possible I would like to see a way to assingning multiple keys (mapping), or way of pressing a key to a specific action. For example:

hold C for prone but tap for crouch.

combine to keystrokes for one action

ability to edit the use the same key for different actions (ie, wheel scroll --changes weapons but also changes scope zoom ). As it stands right know, if you edit default multiple entries then there is no way to duplicate them (except of using default) and there is no way of making alternate duplicates

Also some mice have the ability to tilt the wheel left or right. That is an extra control that is not suported by the game.