Possibly get something like a Chopin Ballade, or Schubert impromptu in your belt. Getting used to longer more expanded pieces in the romantic era may help a lot. It's also good to practice various etudes as well to develop technique and get used to the many technical challenges in Chopin's music.
Themes from Chopin's etudes that are used in the Concerto in E minor.
Op.10 No.1: helps with those arpeggios near the end of Mvt 3 as well as throughout concerto.
Op.10 No.3, Op.25 No.1 and Op.25 No.7- These will help with those serene right hand melody sections throughout Mvt.2 and various sections throughout Mvt.1 (Learn some Nocturnes for soft touch and arpeggiated left hand accompaniment)
Op.10 No.5- Rhythmic accents in the left hand with right hand sixteenth notes can help with much of the last mvt. (Learn some Mazurkas as well, because the last mvt. utilizes much from the polish dance)
Yeah, there's probably more etudes and studies that can be of great help, but those are what came to mind.
Here's a quick synopsis
1st. mvt.- Learn a Ballade or some other self contained work from the romantic era. Study and learn some piano sonata's, because it deals heavily with thematic material, and is in sonata form structure.
2nd. movt- is like a really long nocturne. Study some Chopin Nocturnes. your call which ones.
3rd. mvt- Study some Mazurkas or polonaises for a sense of rhythm and accents within the polish dance
Etudes will help you out with ALL aspects of the concerto, so learn these while learning a ballade, sonata or few mazurkas.
I am basically learning some other stuff before tackling this concerto, but I have studied it in length, and it is my favorite piano concerto. Best of luck and have fun with it
