Sounds like a good, well-rounded arsenal. Personally, I'd drop the 3 single-shots, substiture a .22 revolver with interchangeable cylinder for the auto pistol, and add a .357 and a pocket pistol. Also a powerful .22 air rifle.My preference is a stainless 10/22 ruger, a stainless auto 22 pistol, a mini-14 in stainless, 870 or mossberg 12 gauge, a single shot shotgun and a single shot 22 rifle and a single shot 223
I have a couple old 12 ga single shots, but they were handed down to me.The stainless 10/22 for instance ,fitted with the synthetic stock is considered all-weather ,the negative of course of stainless is the glare factor ,not only to the shooter but also it may give up your position to hostiles.
On the other topic, I don't see the point of owning a single shot "anything".