You can never get enough of these small jams strategy games. Very nice entry.
I'll start with a bug I've found : in the main menu you can softlock yourself by pressing left or right. My guess is that the level choice button is already active before the player hits start.
The game itself is pretty great, simple and elegant. I love how you've circumvented the need for pathfinding by having the player make each move themselves and how each boats orientation double as a faction market. Very clever way to work around your limitations.
Not having a range indicator when aiming a ship was a bit of a bother but then again this was also the case for fire emblem 1. The great thing about well executed simple concepts is that every bit of clunk just add to the gameboy soul. Nice one.
All around very good entry, I especially appreciate having the option to choose a starting battle. Always useful during a jam.