I think a lot of people have not thought about this with logic and common sense. First don’t pick a standard or common round most people are going to go after that because that is what they all been told. Second nothing high powered or designed for accuracy due to most people don’t know how to shoot and you don’t have time to learn. Third most important depends on environment. 1. Pistol M&P 5.7 small holds a ton of ammo light weight shoots flat low to no recoil. 2. Any shotgun and buckshot round no need for slugs’ weapon is meant for intimidation and hunting purpose not looking to take down deer however squirrel, rabbits, and the odd bird here or there. 3. Most people would think some form of assault or hunting rifle wrong again unless you in forest or open plain no need. Here you bring something designed more as standoff weapon you bring a p90 send a lot of fire down rage fast so you can get away. So, you are carrying only two ammo types three fairly light weight weapons. All designed for survival and self-defense.