Have you ever considered designing your own card game outright? In addition to your mtg create-a-cards.
Hi there, I'm Talen Lee. I'm the designer of over forty card games, which you can check out on our website, https://www.invincible.ink/games/media/tabletop/ or you can check out print-and-play versions of them over on itch https://invincibleink.itch.io/