I love these! I recently designed a few decks of playing cards of mathematicians for my dad as a gift, my favorite part was designing the backs: a zeta function for the pure-maths deck, a Moore curve for the computation one, and two interfering waves for the physics one.

Actually, I can share the link if anyone is interested (because this is the "what have you been working on" thread and this has been one of my more fun projects): https://www.thegamecrafter.com/games/mathematical-minds-thre...

Same thought on marketing - where to advertise where people would appreciate this kind of thing?