RE: small game/ varmint rifle?
From what you've described, I'd have to recomend a 25-06. Easily available ammo in a variety of bullets. Or you can roll your own . I say this because you included wolf in your list.
And it is still big enough for deer, bear, etc. You may want to check your local regs regarding legal calibers for all those animals. They may require a bigger caliber than .22 for the wolf.