I have several quests tied to various NPC's on my server, and what I'm hoping can be done or implemented is that if a player has completed a quest that they cannot do (at this time, or ever again) That the quest be removed from displaying in the list they see when speaking to that NPC.

I think it might a little confusing to some people to see a list of quests an NPC has, but they cannot do them again/right now.