I liked the game overall, but I was disappointed that there wasn't more enemy variety, actually. For much of the game, this is made up for by the fact that you don't know that there is not much enemy variety, and you are imagining that there is all kinds of shit out there in the murk ready to get you. But once I realised I was getting to the end of the game, I kind of felt "huh, I expected a bit more." There are the medium-sized enemies, which are all pretty much the same, and which you are all but immune to once you have the Cyclops or the Prawn. Then there are the Reapers and the Crabsquids, which are pretty easy to avoid, and even easier to just smack around with the Prawn suit. Then also the Sea Dragons, which are pretty much the same. The one time one actually noticed me and started breathing fireballs, I just jumped over it, landed on its big dumb head and started punching it until it fucked off and floated away through a wall. Much of the difficulty of the game really comes from the player's initial lack of knowledge/ fear of the environment that they're in, so once you've gotten past this what you're left with feels a little empty.
Given this lack of real content, I felt that the endgame really dragged. Once I knew I had pretty much seen everything and could go anywhere in this ocean world, the appeal of grinding up all the resources needed to complete the game was really lessened. In the end I only built about half the rocket and then gave up. It should have been maybe 20 hours long instead of 40.