What I had in mind would be like maybe somewhere in the game you hide like treasure coves that once they are found you move the cove somewhere else and put new treasure inside. In order to find these you could distribute treasure maps in limited supply around the map to different characters randomly. They could sell these for things they need or search for it themselves. The maps would have a map a couple minimaps around the area of the treasure cove. Also they would tell them the direction of that area relative to a general marker that treasure hunters might know of (i.e. Constantinople or some other city I haven't found). A way that you might know you are getting close is if you start incountering trolls or wolves or some other savage, aggressive creatures (I'm sure other treasure hunters would be aggressive for treasure).
The kind of treasure I was thinking of was maybe like a sword that cant be crafted but is very powerful, maybe a buttload of gold

I know that there has been multiple posts with treasure related ideas, not only are they dead, but they aren't fully dedicated to treasure not planted by players. I don't like the idea of a quest based game, but a little treasure would be cool.