Generally a fun concept, but I think the combination of having the platforms be further to the left and right as well as up and down, with the first person perspective, kind of killed my personal enjoyment of it. It's extremely hard to judge depth using just the mirror, so I spent several minutes trying and failing to pin down the second to last platform of the first level, leading to a great amount of frustration.
I think if you want to keep the platforms as they are, the best solution would be to either include and option to swap to the mirror world perspective, or to play in third person. Possibly both, in fact.
Otherwise, fun idea, hope to see more at some point.