I beat this in 45 seconds (but with 1 death... so I guess it doesn't really count!!)
I really enjoyed celeste, its mechanically great and the story is proper good! Despite the story in your game maybe not hitting the same highs, the mechanics were still pretty on point and added an element of challenge. The downside is there was the wall jump you'd implemented but it wasn't really needed / used in your level design - which was a shame cause it felt quite well done!
Final thought - avoid using just one ground check in the centre of the character - as it helps feel more forgiving!