IC: Pirates!
I ran Skull & Shackles, the pirate game for pathfinder. We found that as the players got more powerful, the ship and the crew didn't matter very much. I hope you are able to find ways to mitigate that.
I'm a little surprised you want to create a game set in more-or-less historical Caribbean. All the colonies were founded on human misery. Not what I would call a fun setting. For my pirate game, I've made it a lighter tone setting.