I've looked at the lh only 10/3. Very challenging. I quite like the lh Butterfly as well.
I don't know why I didn't make this observation before - is your piano stool moved up somewhat to the right? I ask because when I've worked on lh only pieces I have been advised that it can be helpful to actually rotate the piano stool (and body position) a little, so that the left hand side is slightly further in than usual, but the right hand side slightly further out.