Crocodiles and alligators are freshwater, so that wouldn't work.
Zombies? I think that idea is exhausted at this point.
I agree there should be other enemies, but I think giant squid, bigger sharks and seals would be more appropriate.
I disagree that the fact that crocodiles, and alligators are freshwater should matter, it is a game, and they are allowed a certain amount of creative license, as for zombies, while I agree they are very common, especially in the crafting genera, there is a reason they are popular, they are almost always a threat, although usually not an unmanageable one, and they are fun to kill.
Bigger sharks, and squids would, in many ways, be more of the same, they would be a threat in the water, or to the raft, but at this point, either of those would just a boring annoyance, or would fundamentally break the game, we need an enemy that challenges you in a way the shark does not in the mid-game, something that is more a threat to you then the raft, because honestly, your raft is pretty secure at this point, and you don't really want that to change.
As for seals, I think they would be bad because people would not want to kill them, seals are generally seen as cute, and sympathetic, and having to fight them would probably not do the games favors.
yes, but you forget one crucial detail: This is a video game. guess what, metal doesn't normally float on water either, it does in the game though. Why? Because it's a game. wood, barrels, and leaves don't magically come out of the either to drift past a raft being moved in a direction by some unseen force despite there being no evidence of sails either. But in the game they do. Why? Because it is a game. If the developers want to add a crocodile, even though you seem to be floating in the ocean, the developers will add a crocodile to the game. Why? Because it is a game. If you have some comments about the merit of the idea, maybe suggest some possible alternatives, I'd love to here it, if you want to talk about how crocidles are fresh water, despite the fact that that comment has already been made 3 times now, I will say it again. This is a game.