It really depends on where you're coming from. If you're coming to CP from the west, then SFGAm would make more sense. If you're coming from the east, SFWoA would. From the south PKI would. None of these parks except CP and SFWoA are
that close together. So if you told us how you're traveling to CP (and where you're coming from) it might make the choice more obvious.
If traveling long distances didn't matter, I'd probably chose in this order: SFGAm, SFWoA, Kennywood (might as well throw that in!), PKI.
-Nate