Hey i noticed you were giving in depth reviews on other peoples games so thought you deserved the same respect, its really amazing what youre doing out there!
So just to start this game was absolutely beautiful with the piano and the pixel art, it was a joy just from that to be in the world which is something not alot of games are able to do (i remember from the ludum dare the only game that did this for me was about playing as a rock!) , the game was a absolute joy but of course it isnt perfect, though if you and your team wants to get it to closer here are some things yall will want to conside (i will also include potential solutions but there are infinite ways to solve any problem so dont just go by what i say):
Problem:
The Dialogue being real time was really unintuitive, after i read the text i found myself clicking to skip but to no avail, sometimes i would click at the same time as it skipped so i thought there might have been some weird timer system until i just let go and realized it was playing on its own. You were safe to give the players a generous amount of time to read which means no one missed any dialogue but still since everyones reading speed varies alot of players would have to sit through some unnecessary precious moments without playing the game.
Solution:
Have some sort of button to skip, usually its just a click/press to fill out the text and another click/press to go to the next text box, this works very effectively since it allows anyone to read at their own pace.
Problem:
The spirits description would go away to fast, for some people it might be the perfect amount of time to read it or even to much time but for me it went by to fast and a couple of times i just had to figure out what changed on my own
Solution:
Dont let the text disappear until the player confirms! it can be a simple button press or if the player attempts move that can make the text go away but just something that gives player the control to read at their own pace. your words arent of any use if no one can read them.
Problem:
The level design can be unintuitive sometimes, I found myself at the rocky area where you had to wall jump early in the game and i thought it was going to be a learning section, after a while i just gave up until later i realized i needed a spirit for that. I also almost did not even notice the top right quarter of the map until i accidentally jumped into it by hopping around, i just assumed it was natural decoration and not at all something for me to jump on.
Solution:
As for areas where you cant do something that feels like a core mechanic like wall jumping or something like that simple text can go a long way, i know it can ruin some of the silent elegance you might have wanted to pull off without having the text but text can be a really powerful tool when used sparingly and correctly, just something like "you cannot wall jump yet" would have communicated to me that somewhere i can gain the ability to wall jump and when i do i will come back here. maybe thats just a problem for me since this seems to be mostly targeted to metroidvania players and i have only touched like two in my whole life. though as for the platform i nearly missed that feels like a much more universal problem that could happen to anyone whether they play metroidvanias regularly or not, some simple solutions would be to make the platformable parts contrast alot more from the non platformable parts, or have some sort of item or collectible ontop so that i would know "oh i can go there".
Aside from these issues the game remained a solid experience and i enjoyed every second of it, the scope is absolutely baffling for a game jam game in terms of content and literal size. I really hope you develop this further and i cannot wait to see where you take this! will be looking forward to your future releases.