Hahah, thanks! It does ramp up a little fast, if I made this a full game I'd definitely add a few more rooms between getting the wall jump and reaching that section. In general I'd add a lot more rooms, and design them to be more open and "generally challenging" rather than focused "celeste-like" obstacle courses.
I'm taking a break with the project for now, but when I resume, I'll definitely send you a message about the music. Maybe we can work together sometime, who knows.
The ledge thing also bugged me. I had a solution for it, but that caused other problems, so I put it on hold until I implement an elegant system for it. Controller support is another one of those "more time/larger game" things but I'll keep it in mind!