1) Brain Stem.
2) Brain. Specifically from one side to the other, not front to back. Ofc front to back is still horrible tho.
3) Heart.
4) Aorta. Artery with most blood flow.
5) Other Major Arteries (Femoral, Brachial, etc).
6) Lungs. Also right behind rib bones, which if shattered, can cause additional damage.
I'd say past these, while there are certainly important vitals that would be bad to be shot in, like the liver, these take the cake. Maybe I missed some, or have some out of order? I'd say even more specific than COM, the chest (nipple line up to upper-mid chest) in between the nipples is optimal. Say you shoot low or high, you're still hitting vitals. Same for shooting a little left or right.
Factoring in ease of hitting target, bones to cause additional damage, amount of vitals in one area, and close proximity to other vital areas, in between the nipple line from the nipples up to the upper-mid chest seems optimal.
I would aim for the heart area. If you shoot right you hit lung. If you shoot left you hit lung. If you shoot high you can hit aorta or throat. If you shoot low you hit liver (not pictured). If you hit on target you hit the heart. Seems you can't lose. Input?
View attachment 964980