I humbly beg you, don't learn op. 57! Everyone's doing it! Everyone! Not to be rude, I'm sure you could do it, maybe even a really good performance but do you have any idea how awkward it would to be take your version of Appassionata to a master class with a straight lineup of eleven other Appassionatas? Think of the awkwardness! Think of the children!
Well, most people would ignore this advice, so feel free to.
[/end rant]
I agree with everything the previous poster said - another Beethoven non-op.57 sonata would be great, Chopin etudes are useful, Czerny is not music. All of WTC is doable (minor hint - don't start with a six page fugue). Some doable Beethoven sonatas are (off the top of my head) op. 26 (with the variations), op. 31/3 or 31/2, op. 90. I'd recommend 31/3 or op. 26 most.
(edited for mistake)
Or you could do one of the few works existing in the non-Beethoven repertoire - like say a Brahms intermezzo or rhapsody, or Prokofieff's 3rd sonata, or anything by Chopin...
$0.02 from
[Rach3]