I think it would be fun to add an immersive 3D space that you can walk around in, where every cosmetic you've bought or earned is displayed. Weapons are hung up on the walls, clothes on rails, titles and awards framed, tools in glass cabinets, maybe even a huge warehouse type space to run around in with all the ships you've bought.
In addition you could have a treasury with a visual representation of the amount of gold currently in your account.
I think this would be a more exciting way to watch your collection grow than just seeing a grid menu, and would encourage players to spend their gold and ancient coins, especially if there was the option to invite other pirates to walk around in your space. I also think players would enjoy taking screenshots and videos of their collection and their piles of gold to share with the community.
Since this would be a purely visual effect and would not offer any strategic advantage, Rare could charge ancient coins for the privilege of having one of these spaces.
Given that all the rewards in this game are cosmetic, I think this would be a nice way to let people enjoy the fruits of their labour.
