Fantastic idea. I won't be here (something something, sister getting married, more important...) but this definitely has the dragon stamp of approval.
Just as a question, though, are upped and unupped versions of a card considered the same card for the 2 card limit? I'm assuming so, but you might want to clarify, particularly for cards such as toadfish/pufferfish; somebody might conceivably try to bring 2 of each of those, thinking they are different cards. Same thing goes for cards where the name changes when upped; 2 flooding + 2 inundation, 2 phoenix + 2 minor phoenix, etc.