I also changed some numbers around that my whole island would only need 1 marketplace 1 church 1 chapel 1 tavern. i had 4 flagships with speedboat speed and like a 1 mile shooting range like a destroyer.
So when i start a game i looked for the corsair place got a marque letter and a boarding hook. the good thing about it is that its only the flagship. Yes sadly i figured out that editing you flagship speed shooting range, cannon power does affect the other flagships too.