Interesting idea but...
Look, I really liked the idea. I even liked some elements of the way you navigate. However, there are many things to criticize about this game, which you may or may not be attached to for artistic reasons.
For one, you can't throw multiple balls at the same time. You might as well be able to since your one "ball" magically reappears in your hand after every throw.
Second, for short levels it's only a nuisance when trial and error is better than your normal abilities. For long levels it's a major pain in the butt. The spikes and pits played a major part in this. The pits weren't so bad, it was the spikes which were impossible to judge their position correctly. The ball simply disappeared, they were invisible to echo, and you could even run into the same spikes repeatedly because even if you died on them it was still extremely difficult to judge their position sometimes. Finally, the ball stopped working halfway through the game which meant that spikes became completely and uttery invisible to me with no way to detect them except when I died.
Then you started getting spike happy. I watched the walkthrough, tried to follow it, then at the end of one level there were ever more spikes you'd never know were there from the walkthrough. After that I got fed up and stopped playing. I had given my fair shot at the game and it wasn't worth my time to play it anymore.
Your concept is more interesting the less you force your player to use trial and error. Your game is more fun the less you put random spikes everywhere and switches that kill you. This could have been a very, very different game, but honestly you chose probably the easiest tack to take for it and made it mostly about dying repeatedly until you get to the check point. In the end that made the game pretty cheap and I felt less like a blind person making their way around and more like a player subject to abuse by the designer.