Today, I mostly tried to rough out specifications for different kinds of decks. This eventually got me inspired to try some improvements to my representation. Those seem to work, but while testing them, I discovered that my "creative" use of the type system didn't quite work, and I'll have to rework some of it to get consistent and desirable behavior.
Thinking about this a bit more, I'll probably have to drop the "type" concept altogether and focus on making the mechanisms for generating instances explicit.
I've got some ideas here that I think are good, but I spent all day fighting off kind of illness, and right now I don't have what it takes to keep up with trying this or writing any more about it.
I have to wrap up now because I feel tired and gross.