I don't think a couple of nocturnes would satisfy the demand of "large romantic work", but if you do a complete opus, it might be okay; ask some of the more senior members.For the 20-21st century work, if it is allowed to do Impressionism, then I'd suggest maybe:Debussy: the complete Estampes, or a piece from there. Equally beautiful are Images I. For less technical demands, you could try Images Oubliees or even the Pour le Piano. You could also do a movement from one of those works if there is a time limit.Ravel: the Jeux d'eau is a nice piece, but very technically demanding. Could you tell some of your current repertoire, so we can get a feel of what you may want?Prokofiev: Prokofiev's Sonata #2, IV is very popular. Among the less dissonant works are the 10 Pieces from Romeo and Juliet. Usually, people choose movements from the 10 pieces. Another, more violent option is the Suggestions Diabolique Op. 4 #4. Barber Barber's Excursion Op. 20 #3 is very beautiful. Written in 1945, it turns a simple tune of "On the Streets of Laredo" into an expressive work.Shostakovich Shostakovich wrote some Preludes and Fugues, but it might not be very good to have 2 P/F's on your program. However, you might think differently.Tcherepnin Alexander Tcherepnin wrote Bagatelles Op. 5, some of them which are exquisite (but may not be to your liking if you dislike dissonance.) For his less dissonant works, his Concert Etude Op. 52 #3 "Punch and Judy" is fantastic, if you can bring out the Chinese-ness of it (which not many recordings can.) Gershwin His most famous piano solo work is the set of 3 preludes, the most familiar being the Prelude #1. Zimerman made a fantastic recording of it.GinasteraDanzas Argentina #2 and Danza Criolla #1 are beautiful.Wild Earl Wild's Etude over Gershwin's "Embraceable You" is kind of popular. It is a beautiful piece.Kapustin Check out his Etudes Op. 40; they're super cool. Everyone has different favorites, but my favorites are nos. 3, 6, and 7. However, I don't think it's a good idea to choose Kapustin, it just sounds weird.