Hi guys, I just played your game and think it is pretty nice already. I personally think the challenge might be a bit too hard in the beginning, maybe you should consider to give two game modes, an easy and a harder one as a choice. The game itself plays very stressful. To keep players busy is one thing, but to stress them out another you don't want to have. Scarp metal is definitely too much after a while, in the very beginning you do really need the amount you did add (it could be used for tougher walls and foundations in the end-game, then it would not add up stored in boxes too much). The raft would need some spikes or anything like that to protect it from the sharks later on when you developed and did built all other stuff, because there comes a point when they start being annoying when your base gets too big and you can not run to them anymore in time. Food is fine balanced, water needs 3 of those cookers, but is then fine too.
It is a raft game and no sail to the islands game, I did get that, but maybe you could give the players some more decorative items for building, for example baskets to drop coconuts, shelfs for tools or the storage boxes, bigger boxes would be also very nice. Also I would remove that wood pillar cage around the trees to let them look nicer. Some end-content might only get available after building everything else, maybe by a level up system, like spikes, decorations and maybe advanced cooking recipes, maybe also any better weapon against sharks or tougher foundations and walls.
These are just a few ideas. Seagulls could fly by and drop feathers or build nests and drop in there eggs if you build a house. I had trouble to drop a roof on my house that I did build a bit higher upwards on pillars, no idea if it works at all but maybe you should add thatch for picking it up in the ocean (or the possibility to dry the leaves to get thatch) and a nice roof option to build. I know you called the leaves that swim by thatch but it works rather like fiber that you usually use for crafting ropes, thatfor I believe you should at least let us dry it for a second recource. And a nice roof option is also missing.
Maybe adding an aquarium or pool in the middle of your raft to have some fishes multiply could be nice. Let us sit down in a recline or deck chair or give us a bed to lay down, because the character says often that we would be tired and it could also be used for respawn ;)
Thanks for reading my ideas. Happy developing guys ;) For more help you can contact me in steam.