Crouching would be good for taking cover, or partial cover, behind terrain and objects.
Slightly increase Focused bonus when using partial cover. example; using a crate to stabilize your aim when your target is on the other side of the crate.
Prone would be useful for snipers and heavy rifle users.
Severe reduction in melee aim and damage.
Receives more damage from melee attacks.
Smaller target from a distance but easier to hit up close.
Sneak skill would be reduced when moving.
Movement Point costs for switching between positions could vary based on Agility.
Switching between standing and crouching would cost the same amount of movement points.
Crouching to prone would use less movement points than prone to crouching.
I don't know if you were planning on adding these features or not, but it would be nice.
