Donquixote "The Joker" Doflamingo is supposed to be some sort of pirate boss, so the one on Bonaire/Douwesen may be appropriate. There's a pirate settlement elsewhere on the same island. Another possibility, a bit more complicated, would be to remove Alistair Garcilaso, who is the leader of the Bonaire pirates, and replace him with Doflamingo. When Doflamingo is defeated, be sure to put Garcilaso back, as he is needed for one of the side quests. Either way... ... character #2 could be Mario Figuiera, owner of the tavern in Bonaire pirate settlement.