This game is so cute and fun, and you've thought of a lot of stuff like the tentacle hitting you if you go too far - very nice. Also all the points at the start is a nice idea.

- I think the map could be bigger, it feels a little too small and playing multiple times can get a little boring,  I want to explore more. And with this style you could be really wacky with what's on the islands.

- Maybe some form of offensive? To keep it simple it could be a powerup that auto fires sideways for a couple seconds, or if you wanted to add a fire button that too. But I think it would really add to the vibe.

- Cosmetics! A shop to upgrade your ship - sails, better materials. Always keeps people coming back.