Getting the Doubloons You Want
No, doubloons aren't just random right out of the chest. You've probably noticed that you have more of some kinds of doubloons than others. That's because you'll get specific doubloons based on your pirate class and the world you search in. There are two ways - two "secrets" - to not only determine which doubloons you'll get, but to control what those doubloons are. There is where the database comes in handy. You can use the pages here to see what class gets what doubloons and what each world offers, then plan accordingly.
If nothing else, remember this...
Class = WHICH doubloons you get
World = LEVEL of doubloons you get
Class = WHICH doubloons you get
World = LEVEL of doubloons you get
Whenever you open a chest with other people, you will all get identical doubloons, items, and gold amounts. There will be one doubloon to represent each person that opened the chest. That means if you want a doubloon that only another class can get, open chests with as many pirates of that class as possible. If my Musketeer wants a Jackrabbit Ju-Ju doubloon, I need to open chests with one or more Swashbucklers.
Keep in mind that there are plenty of doubloons that all classes can get. One, two, or maybe all four pirates opening a chest can get these doubloons in place of anything class-specific. It is possible to get the same doubloon multiple times with one chest.
Hunting in higher-level worlds obviously yields higher-level doubloons, for all pirates who open the chest. The level of doubloon is based on the world, so even if a level 5 character opens a chest in Aquila, they will still get high-level doubloons that be the extra push they need to get through a tough battle.