what do you dislike about sounds other than the volume of screamers and enemies?
Honestly, I think variety in how to detect enemies. The first attack in the water filled room, right before the thing starts screaming, I heard it coming because of the movement through the water. I loved that. Same thing with the masked dude breathing heavy. If you're planning on developing this into a longer game, I would try to keep things like that in mind.
Like, for example, having doors make sounds could tip a player off that something came in the room, focusing on footstep sounds, stuff like that.
It's a great thing you have here, don't get me wrong. It's the first time I've been genuinely scared playing a game in a very long time.