First of all, thank you for playing the game and leaving feedback on it :D
I'm glad you liked the sound design ^^ That's one of the reasons why I suggest playing with a headphone, or a good stereo system :) I confess that I was a bit afraid of using basic shapes on it, but at the same time I had something in mind, and I'm glad that you understood it.
I'm sorry that it got frustrated. You see, I did it all by myself, and since it was part of a game jam, I couldn't really beta test it or alpha test it, so I couldn't tweak the difficulty of the jumps, and since I was the one doing all the testings, I kinda got to a point where all the jumping was feeling easy...
I do have a lot of ideas for this concept, and I already have some fixes in my mind for some of the problems that you brought me, like a small bell sound, or something similar close to where the secrets are located, so if you would be paying attention you would know that a secret was close by, changing the color of the water to red, so the player would know that it was dangerous, also, introduce a moving platform early on is a very good suggestion.
If I make a full game out of this, I would most likely address all those issues, improve the graphics, sound, redo the level, expand and would implement a checkpoint system too. Well, as it is, it's a prototype of an idea :)
A little bit of a spoiler here, that lake would lead to a dead end, where you would find another secret ^^;; if you notice, I kinda hid one of the platforms that lead you there in the dark.
Once again, thank you for checking the game :)