I think a DF function would work better however it would take more time to setup. Or they could just make a unique tournament that can only be done in the Battlehall and just increase the range of rewards by Server Cluster. Heck maybe something else that be nice is the ability to buy Platinum packs based on the amount you've earned. So if you've earned 10 Plat Packs through the Tourney, then you could pay 50k or maybe 25k to buy a pack from the vendor but you would be limited by the amount of packs you had earned.