I think this would be interesting, but it may cause a lot of issues as well. If people are really into dueling, and if this gets added and their dueling stats change, it might be catastrophic for them depending on their house and which category of magic on the spell tree they mainly use to duel. The only way to fix this would also be to buy a resort, and I don't think people would want to pay $5 to resort if this affected them.