Just to have a more simplified view to my LEGOverse, I keep the big ships in the Pirate world and only have smaller no cannon trading ships in the "Castle" world. For me the main draw of the "Pirate" world is the ships. To have big ships in the "Castle" world would copy Pirate themes and shift focus off the castles, fortresses, wizard towers, etc, etc.
I like having small ships to add futher detail to a faction or nation to show it's complexity(or not). Small trading groups that us those small ships are cool, but it's the noble kings/queens, evil tyrants/wizards, good wizards, merchants, town mayors, farmers/peasants, armies, castles, and stories to explain it all that are the main components of my Castle world.
Power corrupts, and absolute power corrupts absolutely!
Despise learning and make everyone pay for your ignorance.
The water that floats a ship is the same that sinks it.
My LEGO figures keep me from being evil, drat!!