I like the game, although I think several features could improve it and make it more complex:
-A Story Mode
-A Survival Mode (Where it gets harder and harder over time to survive, with the goal to last as long as possible)
-A Multiplayer Mode
-More dangers aside from the Shark
-More resource types
-Being able to sail on the raft
-Differently sized islands to go to
-Different weapons that deal different amounts of damage
-A ranged weapon, such as a bow, or perhaps the ability to use the hook to damage the shark
-Decorative items, to make the raft look unique
-More types of fish, more plants, and more types of food in general
-Raft fights/Raft merging (either conquered rafts, or abandoned rafts)
-Different difficulty levels, for example on easy there may be one shark that doesn't have a lot of health and doesn't deal too much damage, whereas on hard there may be two sharks who deal more damage and have more health
-Diving in the ocean, with things to explore such as reefs and shipwrecks