If you apply Einstein's Theory of Relativity, then apply it onto the Riemann Zeta Function, and put the output along with Euler's Identity, apply Baye's Theorem, they are all the same difficulty.
Chopin: Ballade no 1, Ballade no 2, Ballade no 3, Scherzo no 3, Scherzo no 2, Berceuse, Polonaise Heroique , Beethoven: Waldstein movement 1, movement 3; Appasionata movement 1, movement 3. I'm searching for next repertoire. I' m quite sure that the Berceuse is significantly easier than the rest, but i don't know the distance of difficulties between that one and the others( for example: ballade 2 or scherzo) if i learn both of them at the same time...
Beethoven: Appasionata 3<=Appasionata 1<=Waldstein 1Chopin: Polonaise Heroique<ballade 1=Scherzo 2<=ballade 2<Scherzo 3<ballade 3It's hard to compare the sheets of different composers since the emotions are totally different.
Berceuse, Waldstein 3, Appassionata 1, Waldstein 1, Appassionata 3, Polonaise Heroique, Scherzo 2, Scherzo 3, Ballade 3, Ballade 1, Ballade 2But have you looked into Chopin's Scherzo No. 4 or Barcarolle?