This was a fun game. I like the idea of making a metroidvania with one ability that keeps getting stronger instead of a variety of different ones. I would recommend doing something so you can see where you'll land on the highest jump. Maybe zoom out the camera or something. That just added a level of frustration that wasn't necessary. Also, the easy level was a bit on the mindless side while the hard was more frustrating than fun. A third level in between would have been nice.
Overall, great job.