The medical system in arma 2 worked great, and I don't see why it was taken out for arma 3.

A state of unconsciousness allows for further medical depth in the game, adding another possible state of injury
(right now we have perfectly fine > shaky aiming > only walking > death, when instead we could add unconsciousness to the list).

If a person in real life gets shot, they go into shock. If they are shot again, their status will worsen, shock will increase, and they will be severely crippled. However, if they are shot again, they would not instantaneously die. Nobody gets shot and instantaneously dies (like in the movies).
Instead, the person would enter an unconscious state as a result of traumatic shock.
The arma 2 system also made medics an asset, allowing for unconscious soldiers to be brought back into the action. Without a medic/CLS, downed men would have to be carried to medivac by other soldiers, and would have to be revived elsewhere (perhaps at a HEMETT/Zamak medical).
Now in arma 3, any soldier can bring someone back to combat efficiency with a little first aid kit, even if the soldier is at 1% health, an extremely unrealistic implementation.

We should not have to use mods for a feature that has already been implemented into an arma game, and should be implemented into the current one as well. The animations already exist, they only have to be assigned to events within the game.