If you can easily manage Chopin's Scherzo #2, then it's likely that you'd find many of his works not too difficult. Ballade #4 and Scherzo #4 are the more mature works, and I think the challenge will be more about musical / communication than technical.
The diploma syllabus of ABRSM and Trinity (both UK) put the 4 Scherzi, 3 Ballades (#1,2,4), Polonaises #6 & 7 in the same level (licentiate). Other works also on the same level incl. but not limited to the concert and paganini etudes, transcandental etudes (excluding #1), Hungarian rhapsodies of Liszt.