Just thinking. I know there are some of you that have millions of gold pieces (sadly I'm not one of you) but you have nothing to buy with it. So how about a cross server trading system?
So players could take any item to a central bank as trade goods and then other pirates anywhere could try to buy them. The reason for this would be to unlock rare progression achievements.
Say the crate of secrets that's apparently worth £25,000 could be worth £1,000,000 to a player who had never found one before. A set of 10 fort chests could be worth way more to someone looking to unlock achievements. Kraken fresh, rare fish, even bulk loads of common fish could be traded.
This would also allow Rare to introduce even rarer spawns which to a player would be worth a lot more than a NPC would pay.
I personally would prefer to find these items through hours and hours of adventure and discovery... but it would help solve the gold surplus i keep hearing about.
Also for us poor, pirates whose gold burns a hole in out pockets and need to purchase every cosmetic going it would give us a way to sacrifice achievement progress for gold