My pick is a rifle, or carbine actually. Like ShieldWolf, I'm not much of a pistol shooter.

Concealment is not something I really considered, however. My thought was, if the poo's really flying, one guy with a rifle minding his own business shouldn't attract too much attention.

Maybe that's not a good assumption. A solution may be to get a bigger civilian style duffle. A small one currently holds my L2 gear, which acts as kind of an organizer while in the bag. I'll experiment. A larger one may be able to hold my carbine near ready.