Having played FFIX, I always thought it was fun that the cities/locations themselves also had cards that represented them. I think it would be great in XIV to have cards for several locales and seasonal events to celebrate the diversity of landscape within the game!

For seasonal events, the cards could have a different design per year, and added to mogstation for those who miss out the following year. You could name it something like "Heavensturn 16".

To add to these, you could even consider things like X-Potion card, Gold Saucer card, Crystal Tower/Void Ark card, Enterprise card, Adders/Flames/Maelstrom card (pvp!). The ideas could be endless if the categories of cards were expanded to more than NPC/Boss/Enemy/Character cards