Absolutely loved it. Not too obvious with storytelling, not too cryptic. Music felt very natural, all tracks fit together. Absolutely sold on full release day.
One aesthetic idea: your character should bob along to the beat of the song you're listening to in battle instead of a constant pace despite the song's tempo.
A little visual tweak; during battle, being in each of the five columns should have a different view of the character (facing back to the viewer in center, facing more towards the right when on the left, facing more towards the left when on the right columns). This way your character is always focused on the actions of the enemy during the heat of battle.
Enjoyed every second. Would love more puzzles too, the tone puzzle was a good change of pace!