Show in Quest Log (If it's empty or something) WHERE u can still find available quests.
I like to see myself as a perfectionist, currently working on Cantha (100%+vanq), already done with Prophecies. One of the MOST annoying things I find, is the stupid green marker above someone's head when U didn't do his quest yet.
Now, most people do know how I feel, and knowing that after you "completed" the campain, there still is this one guy in random outpost/instance X that is waiting for you to come accept his quest is eating me alive. (Ok, it's not that bad, but still

Anyways, simple suggestion: Add NPC, option in quest log, whatever that shows U where U still have to do a quest, ...
Repeatable quests will dissapear from this list after U finished them for the first time
