Hehe, so I’m not the only one liking the colors schema, that’s nice to hear! You’re absolutely right, it’s far from being able to be called a “game”.
I like your Idea of iterating on it, to make it a fully grid based DC, like also on the Boat itself, that could be something worth iterating on - even tho I liked the DC part combined with free-movement but I see it also as a fully grid based one. Also as you mentioned it, the things one could be doing on the boat could also be expanded very much on.
I also was thinking on having small Islands where you can leave the boat to gather resourced and also have the occasionally combat :)