So this idea is very basic and straightforward but it could make it possible for the devs to easily create many "new(ish)" cards by adding affinities to every card (or even add all the 4 affinity types to every card).
I could imagine a poll every once in a while with a few cards to choose from and that card would get a new version with an affinity. The community could even come up with ideas about the different special attributes a card could get. Let's say we vote for Contruct (because that's my fav unit) and a frost affinity. After that we could discuss what could be the special to that
