There should be different types of quests:
1) Entry level quests - Simple, low reward quests that are always available for a quick buck when you are short on jing; getting rats out of a cellar, etc.
2) Reoccurring quests ? Always available, these quests become harder as player?s skills advance; the rewards become higher as well. The quests rotate around; getting rid of pesky mobs, knocking off bothersome thugs (NPCs), gathering special resources from the corners of the wild, and running messages to the wrong side of the tracks.
3) Standard quests ? Unique quests that are left open for some time and allow everybody a chance at a special item or reward. These quests would be introduced on a regular basis so we can always have a special challenge available.
4) Special quests ? A once in a lifetime, short lived quest that give a few players a chance a very special item.