Bach:
WTC (you could probably handle most of the stuff in there)
Chopin:
Polonaise op 40/1 (if you haven't played it already)
Polonaises Op 26
All Chopin preludes except for B flat minor, G sharp minor, and F sharp minor would be fine
Mazurkas for musical benefit (and good sightreading!)
Etudes Op 10/3, 10/6, 10/11, 10/12, 25/1, 25/2, 25/7 (choose one of them, don't try to play them all!)
For Russian music, Rach is my favorite:
Moments Musicaux op 16
Elegie op 3/1
Prelude in C# minor op 3/2
Prelude in B flat major Op 23/2 (I think? Haven't messed with the preludes in a long time)