OK, I'll try my best.
I honestly like the mechanism of this game. So naturally, I would like to use it without hassling. While I think the individual actions are pretty well crafted (e.g. throwing, double jump, etc), I always get stuck between the transition of each action. Remembering which button does which was a bit puzzling enough. And don't get me wrong, this is likely MY issue of not being good at handling the ASDW key input. So, considering there could be more people like me, it might be a better idea to introduce one mechanism per stage. First, move, second, throw, third, double jump... so on and so forth.
Also, I found a small bug in the title screen where you can actually fall off the left side by accident. I was trying to get used to the control and accidentally threw the machine piece, then I fell off as I chased it.
Once again, I think it's a cool idea and I admire you trying to polish it further. Good luck! I hope this feedback helps you somehow :)