This might be a little too much, but while I was playing I realized that if your looking for good loot you generally only need to check 4 structures: Large Pirate ships, Large Bandit Camps, Large marine bases, and Marine Battleships. While these structures can be difficult to raid and do have at least one high level loot pool chest, with more than one person, or a devil fruit user they don't pose that much of a threat. So I figured that if I wanted a higher level structure I should recommend it.