I think your poll is useless.
And only one that knows what you mean with “Get out the firepower” is you.
In a world with weapons I don´t see how someone choosing “gather food and supplies” would ever prevail against “getting out the firepower” which I assume you mean form an armed force that takes what they need.
So for me firepower is included in supplies.
I´d get firepower first, and then go for medical supplies and then other supplies.
Given the fact that there´s no “civilization” left there is survival of the fittest again.
Fittest in predatory terms means healthy and strong. Strong either as individual or as group.
No civilization left, no one to produce weapons or medical supplies so stack those up to stay fit, hunt and protect yourself.
Everyone can kill animals for food, gather berries or grow some fruits.
Not everyone can produce weapons, ammunition and medical supplies.
And as long as there are things that are rare and others want to have, you need something to protect yourself.
So basically i´d get heavy, get like minded peeps, get medical supplies, and then start a new community somewhere. Protected by weapons, healthy with supplies and making stuff for the daily needs.
That boiled down I wonder who would answer here, “i´d go against all principles of civilation and randomly kill people to survive” - as I said, IMO the poll is not thought to the end.