I had a crazy idea to suggest but I don't think it would get approved. I think Uznair/Aquapolis and future iterations of the treasure content should share a hub zone similar to Triple Triad Battlehall where people meet up and group up. Heres the catch. Instead of making it so when you open a chest in the world you have a 50% chance of getting a portal, instead you get some gem/token that is used to open up the passageway to the specific treasure area. This way parties can stock up on them or trade them to an NPC there for other ones they wanted a specific item from. Maybe only downward though.