Hi, Dorothy. Thanks for your comments.
I imagined Facets being more of a showcase for what the WL can do, or what one can do with the WL, rather than being a poker deck. The notion that I might do four instead of three card groupings never occurred to me. Since they don't have ♠-♥-♦-♣ on them, I'm not sure there's a good reason to do so. It would take a little extra work if one wanted to make Facets analogous to a poker deck, but it could be done. Now that I think of it though, two strengths of the electronic version of Facets, random generation and interactivity, would be lost in a physical deck.
The idea of QR codes for the WL expressions is intriguing. A person could hold it up to the computer's camera to paste the expression into a notebook. If I ever turn Facets into a physical deck of cards, I think I'll use your idea. : )