Leo Ornstein's Ballade is a profound, modernist exploration of sound and texture, often featuring dissonant clusters and complex, layered textures. It represents the composer’s 'futurist' phase, moving far beyond traditional tonal boundaries.
Navigating the complex, non-traditional notation and the high-density layered textures is a significant technical undertaking.
Comparable difficulty and character — good candidates for what to learn next.
Ballade, S108 is rated Henle level 8 of 9 — concert repertoire, roughly diploma level. In the RCM system it corresponds to about level 10.
You should be comfortable at Henle level 8 — meaning you can already play level 7–8 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Ballade, S108 lasts about 9 minutes.
Ballade, S108 is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include Ballade, SO 108 by Leo Ornstein, Ballad (Das Geisterschiff) by Carl Tausig, Asturias (Leyenda) by Isaac Albéniz — see the full similar-pieces list on this page.