i propose a 3 tiered system for trading fees. The purpose is to attract bots / day traders and large volume traders.
Tier1: Fees as they are now
Tier2: 25% lower fees for addresses with more than 10 trades a month / 5 digit usd volume
Tier3: 50% lower fees for addresses with more than 60 trades a month / 6 digit usd volume
numbers are subject of change but you get the idea