I just remembered something:
In Niffleheim Town, there is sorta a quest about gathering piano keys and bringing it to the large piano in one of the houses.
What happens after that?
Another is the Grave in the Far North-East part of the map where you asked some questions I think,
(The one where you can summon half a dozen orc skeletons). Again, what happens after that?
It just popped in my mind and it keeps bugging me.