This game has potential to be the next little nightmares, limbo or inside. Love the game so much that it has left me wanting more. To see more of mira and how her mind works. Please continue to work on this game or a game similar to this because it was so fun and I would love to play this game again if it was ever released fully.
Theres wasn't any problems in my playthough however, I do have some improvements that could be made to the game.
1. Make the game bigger by adding more areas to the game. The downfall of this game is that the game is way too short for the player to have a clear understanding on what the storyline is. Adding more areas and telling the story through enviromental storytelling and through dialogue (It can just all be enviromental and then leave it up to the player to piece everything together) will keep the player engaged longer and be wanting a lot more from the game.
2. Adding a crouch and mantle mechanic. If you look at similar games like the ones I have mentioned, they all have a crouch and mantle control mechanic and make use of these in a variety of ways. Maybe look into implimenting something similar into the game. It just adds more to the gameplay and the experience to the game. Little nightmares has it so everything is climbable as long as you can reach it. Maybe add a similar mechanic to the game.
3. Add some kind of antagonist. I get that you want the water to be the main antagonist but you also have to think that the player is exploring a mind of a child. There imagination can conjure up unspeakable monstrosities. Take advantage of that and add more enemies to the game to give the game a more challenging feel but don't forget to make these monsters fit into the story of the game. An nexample of this would be something like a monster that is linked to water to help tell the story of how mira came to be in the water. I go more in depth in my video so I hope you enjoy and good luck for the future of this game and others you will work on.