I think there could be a sort of random quest generator in the game. Some of these could be...
Government sponsored...
1. Bounty Hunt.
Explanation: For a certain period of time, the city will pay a certain amount of money for the corpse of a specified monster (assuming corpses are implemented).
2. The Tournament of Warriors/Mages/Clan/etc.
Explanation: A tournament will be held in the colliseum. Some limitation might include it to be Warriors only, Mage only, Clan/Party warfare. Or a group versus a series of increasingly tougher mosnters.
Individual sponsored...
1. Carrier Mission.
Explanation: An NPC ask a player to deliver some items or cargo to a destination or another NPC. (Low reward in general).
Will think of more later...