Pressing left to confirm was certainly an unusual choice. Considering the focus was on time, I would think simply pressing the direction once would be the way to go, simply using WASD without a confirmation, but I also get it's more meant to be like a joystick in that you are supposed to hold the direction and try adjusting while pressing to confirm. But considering how tight the corners are, I'm not sure this was the type of level design to go for that style.
It being left arrow can mess with your perception of direction even if you are trying to stay focused on WASD, I think space would have been fitting.
As others mentioned, it's pretty difficult, but I think that is in part because it's not the usual kind of game most are familiar with with these kinds of movements. I think you may have been able to get away with less pressure by having a timed amount of moves instead, making the focus more of a puzzle solver where you have to path correctly in a limited number of movements. Or as others have mentioned, a bit more leniency on the easy mode.
On the topic of art, I certainly enjoyed the art you did for it, though I do wish you had some basic sounds even for the movement, or at the least a simple background loop. Overall I felt the love you put into this, it can shine through even if I suck at the game itself.