Basically, I had an idea come to me about log poses from one piece, and it clicked in my mind that you also have integration with the islands mod (because you made it, duh???) so my suggestion starts as a question: What if log poses were added to the game and displayed info about the nearest/next island you could visit? Currently, I'm using the islands mod, but the sea is so incredibly vast that finding anything is much too difficult, tedious, and time consuming - and I'm always up for a challenge... when it's necessary.
I'm gonna try to go into a little detail as I do want this to be read and possibly considered, but what if it worked sort of like a lodestone at the median center of each island mass? (or maybe they're generated on a grid-like system? i'm not sure, i'd have to do much deeper digging to really find out.)
Maybe there could be a log pose NPC that could spawn, or you might just be able to buy a log pose from a merchant that spawns on that island. Eternal log poses also sort-of come into play, much like lodestone compasses, but to be honest, minecraft already has that one handled. (Maybe I'll make a resource pack that changes lodestone compasses into eternal log poses, now that's a good idea.)
I also just recently had a similar idea but it's different in the fact that it would be a UI element instead of an item, and it would point towards an island you have not visited yet...?? I'm not entirely sure how you'd go about scripting those interactions between player and island but i'm sure it could definitely be figured out.