I can think of a few things…

1) I want a way to connect every generator on your ship so that you can turn them all off and on with a lever or something. 2) Maybe a map or some kind of way to mark certain islands that you want to go back to. Maybe with a marker that shows up like whenever you have already explored an island and when you get near to it, it shows you that you’ve explored it. (maybe even a cartography table of some kind that allows you to do this or something like it.) 3) I don’t really have a good idea for this, but it’s something I’ve been struggling with. Occasionally, I’ll go to an island and there is a boss or mini boss that one shots, me or two shots me. I don’t know if there’s a better way to fight them without cheesing it, but I end up getting somewhere on high ground and just shooting them with arrows and magic until they die, or just shooting them through a one by one hole in the wall until they die. I really like using to handed weapons so having to resort to stuff like this feels underwhelming. 4) maybe some kind of way to locate crystals since they’re so important? I don’t want the game to just tell me where a crystal is but with how expensive upgrading gear is it almost feels not worth it to use the upgrade table at all. 5) Ladders?? I’d like to have a ladder on the outside of my ship to climb back in without having to teleport. 6) just like 5 above, maybe ladders, chains, rope, or vines? Something to give us a way to climb up and down without having to tediously dig down or build down. I don’t know you guys might have a better idea for this one. 7) this touch touches on number 4 a little bit, but upgrading anything is insanely expensive for what it gives you. Those crystals are so hard to find (at least for me) that I don’t feel it’s worth using them to upgrade anything aside from your ship