For some reason, the KDE for Windows version of Kpatience solitaire has access to more deck appearances and backgrounds than the version available for Linux. Some of the deck appearances on the Windows version are in my humble opinion superior options. Why is there a disparity between the two versions?

This shouldn't be the case. Can you check your package manager to verify that all packages containing Patience decks are installed?

it would help if you listed the decks missing or the numbers available in each

in my distro there is a separate package for kde4-cardecks-other and in Kpat config appearance there is the ability to get additional card decks

ah ha! I was missing kdegames-card-data-extra. Thanks for the help.