A good first try.
Overall, a good, but not great fic. My main gripe with this fic is that it feels rushed. The writing as such is good, but it feels like it lacks adjectives. Characterisation is good, but many characters come across as somewhat flat. Above all, almost no page time is devoted to the psychological effects of the kind of brutal and one-sided warfare described.
However, apart from these lapses, the fic is good. Good writing and good characterisation, as mentioned. The descriptions of the U.S.S. Wisconsin are believable and seem accurate. The Human OCs are well-written and believable.
Battleships are Magic is worth reading on it's own merits, even if it is by no means stellar. However, Battleships are Magic is the first in a series of fics, and the following instances are MUCH better. Even if you don't like Battleships are Magic, plow through it to open the door to the wonderful 'verse the author has created.