Things I think that should be added:
- Some kind of defense ( sharpened wood planks) you can put on the edge of your foundations to keep the shark away.
- Day and night cycle.
- Up-gradable water purifier where you can boil several cans of water at once or have larger cans so you can drink more.
- Islands you can visit for supplies that you cant find in the water.
- And oars or Sails so you can move your raft.
- The ability to pick up and move items.
- Also music because its pretty quiet in game!