What are the thoughts of adding a town crier npc in each world ? This person would direct you to the npc needed to receive your uncompleted quests. They would list 3 quests at a time and the name of the npc you need to speak to ,to get the quest. They would also only list the quests in their specific worlds only .The job could even be added to already existing npc's like a bar keep where the pirate would go to him to see if there is anyone in need of help, like a wanted board. Barkeeps would be perfect for the job anyway since the pubs are never full of paying customers anyway . It could also cost a little gold to get the information.
This would be much more helpful than running around like a fool throughout the spiral trying to find missing quests ,especially as big as it is .