Upvoted.

I've done this for all vehicles in ACE2. I had to redefine especially AI settings, so they acutally relied on their visibility skills. I dunno how this is handeled in Arma3, hopefully there are more options available to fine tune the whole concept.

+1
In ACE2 we worked with a special ace_hit value for all anti tank weapons and of course minimalHit.
So there would be no need to "fix" all weapons ingame, the lack of an AT weapon variety make it pretty simple.
And yes even the the over 2 year old armor system from ACE2 would be better than this.

+1
I'm using a Magpul MS3 in combination with a S&S Weaponlink. If I need to reach for my backup, I just drop the rifle in front of me to the chest supported by the weak hand while the other reaches for the backup. To strap/fasten the gun, I attach it to the weapon link.