I think Sea of Thieves would be more entertaining and exciting with more cool chest types like the Wailing Chest that cries and fills your boat with water.
Here's some ideas:
CHEST OF STORMS
Once this chest enters onto a player controlled ship, a small centralized furious storm will rage directly above the ship and follow it.
This will be easy for enemy players to spot but will also be difficult to take as you'd need to enter a storm to get it.
BIRDCALLER'S PLUNDER
This chest attracts birds the same way shipwrecks do. Making it easy to find... and to follow. The birds will continue to follow this chest to where ever it is taken.
NECROMANCER'S CHEST
This chest will intermittently spawn groups of skeletons around it. Keep your weapons ready.
CHEST OF THE DAMNED
Upon setting out to sea, this chest will begin to wail, signalling the Kraken to it's stead. Don't stay out in the open water long or be prepared for a visitor.
