You need to be thinking long term
Basically the Port Upgrades were a smaller version of this; larger nations did, as they did their eco better, have a huge advantage in early game due to their well coordinated eco - and were thus able to pump out the "creme de la creme" in much larger quanitity
Now, other nations eventually caught up.
If you now go and think long-term, in a month or two, those larger nations will be able to craft a lot more of those new super boats - This time, it will take the others way longer to get on a similar level though.
I do not see this working out very well for the game.