.22lr - gives a lot of flexibility; handguns and rifles in both semiauto and manual
.223 - bolt & semiauto rifles
9mm - revolvers, semiauto pistols & rifles
.357mag - hand guns and rifles
20ga - a lot of variety of rounds from shot to slug and manual to semiauto.
All of those give me a ton of options & flexibility from young to old, from manual actions to semiautos, from hand guns to long guns, from close to fairly far, from small to fairly large, from fur to feathers, from 2 legged to 4 legged, and commonly available ammo
Swapping the .223 to something heavier would be the 1st consideration if needed.