No offense to the combat infantrymen (who should be compared to Roman soldiers, not gladiators) or the snipers lurking about here (that is, 500 yards away) but those things are of little relevance to someone investigating a noise in their house where they keep the family silver or to a partygoer outside their favorite club at 2:00 AM back in the parking lot. But most of the other stuff is good.
Now about that kill ratio for bullets fired: you are again measuring efficiency the wrong way. Efficiency is winning the war and achieving your objectives. You can lose most of the battles (but not the last one), have more casualties and still win the war. Think like Grant. Lose a battle and advance. Don't be like some generals and win the battle, then fall back.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
Buy War Bonds.