I wonder about "disks." Granted "pentacles" are worse.
These cards are so elemental, labeling them by element, in this case "earth," even if the symbolism involves disks, seems more true to the feeling. If there's to be a man-made thing representing an element, like swords for air, then hm, I guess I'm enamored of coins as the representatives of the material realm, the world of dirt and rocks. I don't know what a disk is in any deck
Anyway. The minotaur is a monstrous male, mythologically. If we tie the Ace to the minotaur, the hermaphrodism becomes awkward for that reason. (I like the hermaphrodism for all the aces; I like the idea of the Aces also showing sexuality as potential.)
Bit of a ramble, this.