Don't do Op. 110.
Reconsider the Funerailles.
By all means do not ever think about doing Op. 25 No. 1 again. The requirement is a virtuosic etude, not an easy etude. I suggest 10/1, 2, 4, 7, 8, 10 or 25/5, 6, 8, 10 or 11
The thought of doing a Schubert Impromptu as the piece of your choice is simply retarded. Here are some examples of what people have done-
Ravel- Gaspard de la Nuit, Miroirs or Le Tombeau de Couperin
Bartok- Sonata
Rachmaninoff- Sonata No. 2, Corelli Variations
Stravinsky- Petrouchka, Sonata
Prokofiev- Toccata or Sonatas
Scriabin- Sonatas No. 5-10
Debussy- Selections from Preludes and Etudes
Barber- Sonata
Berg- Sonata Op. 1
Schoenberg- Op. 11, 25 etc.