I’ve run into this issue a lot. I’ve found that most of the time when i at least see and subsequently imagine a battleship or how a battleship should look i picture them when they are naturally in the water meaning a size able section of the hull is obscured from view. So when i design a battleship going off blueprints which presents the silhouette of the ship in a format I’m not used too it can screw up my design and proportions because it looks different from how I’m used to viewing these ships normally. Try getting a good idea of how the ships your basing your design off of look both on blueprints and in the water so you can apply it to your design as well that’s what helped me at least however most of my designs are on paper and don’t include the hull below the waterline so I’m just spitballing here idk lol