Well done mate. Perosnally Alkan is one of my fav composers. IMO none is harder than THE other and you would have to check the score to see for yourself. Personally I find that both are just as hard. Perhaps scan the piece and play some sections that are really hard and seee if you can deal with it. The thing I know about Aesop's feast is that it is an etude and incorporates all the elements of the precending minor key etudes into the variations, from what I've heard. So you might experience a variety of difficulties at the same time, unlike the Scherzo diablo when you are facing perhaps at most 2-3 factors.
BTW it is ALKAN, not Alcan. maybe it is just your regional variation on his name.
JL