Could make it a game. Each week or month, the user starts with 100,000 fake BTS. The site works just like OK, except there is no deposit or withdraws. It would function just like a centralized version of OL so there's no need for multiple witnesses and committees. The rules,fees and feeds would just mirror the real dex. Who ever has the mist BTS or networth at the end of the round wins. You also add a real BTS entry fee and those who enter would win that pool.