My #1 rule in any dangerous situation is simple. My loyalty,and attention is to my family and those in my charge that are present at the time of action.
I will "seek cover, create a defensiable position /identify escape route and exit." I will not abandon them to bring the fight to the "bad guy" Unless the "bad guy" is coming my way. Then I will do what I can to draw his fire away from those behind me bring the fued to him, and kill him as quickly as I can. GOD willing.
If rule #1 isn't needed . Then I have no problems inserting myself into the action if I'm in the GROOUND ZERO area.
The quickest way to drop a "bad Guy" is blindsiding him when his attention is focused on something/someone else.....