The nocturne in g minor, op 15/3 is a good one- the most accessible of all the nocturnes, and very nice to play.
Are you referring to the nocturne in e flat major, op 9/2? I'm unaware that Chopin wrote a nocturne in e flat minor, and I have a book of all the nocturnes...\
Other works of Chopin's:
Mazurkas (as many as you want!)
"easy" preludes; 4,6,7,20
"Raindrop" prelude, op 28/15
Polonaise in G minor
Waltz in A minor, Op Posth.
Waltz in B minor, op 69/2
Waltz in A flat, op 69/1
Waltz in F minor, op 70/2
Some Mozart sonatas would be good for developing fluid technique, a very key factor w/ Chopin.
Bach never hurt anyone, his two part inventions are a must of the piano repertoire, as are his preludes and fugues (though those may be a bit too difficult for you to play well).