What if, if a player chooses not to lay a claim, then his ship could be his claim. Allowing it not to be stolen or chests looted. Crates could be stolen still. This could be the pirate option.
I mean, it’s not a bad idea, but I doubt many people would use it; almost every active player is in a nation, including pirates.
What if the ship claim could be a mobile settlement / nation? Obvious limitation being storage restrictions of ship size.