Using the toggle controls such as ADS and Sprint in this game does not feel right. The problem is that in most games the toggle is canceled if other actions are being performed.
ADS should toggle off during a reload and when you start sprinting.
Sprinting should toggle off whenever you stop moving, crouch, ADS and shoot.
Crouch works as expected.
Basically whenever you do something that temporarily disable the function, it should just turn off.