Since many of us have the problem of having too many treasure cards why not allow players to use a backpack lock on treasure cards so that way we can quicksell ones we don't need without fear of accidently selling ones we may use for crafting/questing/pvp?
Honestly just give us unlimited treasure card space. I'm pretty sure that making a new wizard to store treasure cards takes a lot more space than a few more integers lying around in a database.