Does this Unit replace anything?

I'm sure this is a really cool mod but if I may, I'd like to add some context to the longboat. It was a type of galley uniquely suited for deep ocean travel, despite its small size. It was incredibly flexible, able to twist with the large waves found in the open ocean. Long, thin galleys will snap in tall waves due to force exerted on the boats. The longboat solved this problem.
HOWEVER there are many problems beyond waves that stopped long ocean voyages. The vikings could only manage to do small island hopping because they lacked the proper navigational abilities that came with mathematics and charts later- the biggest danger to long voyages is runninng out of food and water. There is a hard limit on how long you can be at sea based on the supplies you bring with you.
Longboats designed as transports, which (to be fair to firaxis) is what already happens in Civ V- when Danish units embark, they render as longboats.
I don't mean to be a party pooper :(