My two pence (if not cents) on "show-pieces":
BEETHOVEN
Finale from the following sonatas:
Op.27 No.1, 2 (quasi una fantaisa); Op.54;
Op.57 (appassionata); Op.78; Op.81a (les adieux)
CHOPIN
1. Waltzes 4, 5, 6, 11 and 14 are quite effective, if not too difficult.
2. Scherzos 1, 3
3. Prelude Op.28 No.24 in D minor. Not easy by any standards.
4. Polonaise 6
5. Finale from Sonata Op.58 in B minor
6. Andante Spianato & Grand Polonaise Brillante Op.22 in Eb
7. Etudes Op.10 No.4, 5 (black-keys), 8; Op.25 No.8 (sixths), 11 (winter wind), 12 (ocean)
LISZT
1. Apres un lecture du dante ("Dante Sonata" - I know it's long and hard, but VERY effective)
2. Orage, Vallee d'Obermann (ending section)
3. Transcendental Studies 1, 2, 4, 5, 6, 8, 10, 11 (6 is one of my war-horses)
4. Hungarian Rhapsodies 2, 6, 8, 10, 11, 12, 13, 14, 15 (Rakoczy March)
(mind you - 2 and 14 are formidable, as are 10 and 12, but Liszt's works need frequent sharpening up to stay in shape)
5. Although the "3 Concert Studies" are difficult (especially 1 and 2) they are more musical and poetic than they are show-pieces in general, although each has some sections that are highly showy, such as the wide, climatic alternating leaps between both hands immediately before the slow ending of "Il lamento", and the chromatic running passages in "La leggeriezza".