Any Romantic and Contemporary (20th Century and on) Recommendations?

[saikonozero]

I'm working on some pieces for a piano exam and needed some suggestions for my Romantic and Contemporary pieces.
What I'm currently working on are:
Baroque- The Overture of Bach's Overture in the French style, BWV 831
Classical- Beethoven's Waldstein Sonata, Op. 53 No. 21, mvt. 1
Romantic- Rachmaninoff's Prelude in G minor, Op. 23 No. 5
Contemporary- undecided
Etude- Chopin's Etude op. 10 No. 4

For my Contemporary piece, my teacher has recommended Stravinsky's Petroushka, but I'm not sure how difficult that will be to master, as it seems like quite a difficult piece.
As for my Romantic, I'm working on the Prelude, but I'm not quite enjoying the piece while practicing it as much as I'd hoped.
Don't get me wrong, I do like the piece, it's just that it feels somewhat repetitive when playing, and I guess that the whole march style of the piece doesn't sit too well with me after playing it so many times.
I guess I'd like a smoother of a piece for the Romantic and I've no idea about the contemporary.
I'd also like for the recommendations to be relatively short (somewhere around 5 minutes or less) as I'll need to memorize them and would rather not have to work on something too long.

[invictious]

I have TRIED the Petrouchka. I did not get past the first page after two weeks.

(by that I mean the part after the glissando..and up to tempo)

[fbt]

Copland-Passacaglia
Griffes-Scherzo or The White Peacock

[phoqoo]

My favorite piece at the current time:

Krenek's Sonata 2 Op 59

[dtao12]

I guess I'd like a smoother of a piece for the Romantic and I've no idea about the contemporary.
I'd also like for the recommendations to be relatively short (somewhere around 5 minutes or less) as I'll need to memorize them and would rather not have to work on something too long.

If your teacher recommended Petrouchka, I'll assume you have a strong technique, otherwise that suggestion would have been outlandish. Also, I've limited my suggestions to "short" pieces (close to 5 but no more than 10 minutes).

Romantic:
-  You're already playing Chopin for your "etude" otherwise I'd recommend Chopin since he has plenty of short pieces (Ballade, Scherzo, Etudes, Preludes, Polonaise).
-  How about Schumann Toccata (difficult, but if easier than Petrouchka, trust me). I love Schumann but he doesn't have that many short pieces that are also advanced.
-  Brahms has a lot of great ones -- Rhapsodies op. 119#4 or Op. 79#1 are dramatic and powerful, but if you want "smoother" (as in lyrical) then the Intermezzo op. 118#2 or op 118#6.
-  Liszt Sonnetto del Petrarca, Gnomenriegen, Hungarian Rhapsody #6 or #12 or Liebestraum. 
-  Or one of the Alkan miniatures, for something less frequently played

Contemporary: sounds like this can be anything 20th century rather than ultra-modern, so how about
- Ravel Jeux d'Eau
- Debussy L'Isle Joyeuse or Feux d'artifice (for virtuosity) or Sarabande (for quiet beauty). One of - Shostakovich preludes and fugues are something else that would fit in your time limit and are not overplayed.
- Gershwin Preludes
- Barber Excursions
- Scriabin Piano Sonata #4

[avguste]

For contemporary, I would go with something not often played. Maybe a living composer.
Obviously this also depends on who  is your teacher, where you are studying and how good you are.