This piece by contemporary composer Ana Leira Carnero explores heroic thematic material through modernist harmonic structures. It is distinguished by its epic, narrative quality and expansive dynamic range.
The technical difficulty centers on voicing the complex chords while sustaining a heroic, forward-moving sound.
Comparable difficulty and character — good candidates for what to learn next.
Allegro Eroico is rated Henle level 6 of 9 — advanced repertoire, roughly ABRSM grades 7–8. In the RCM system it corresponds to about level 8.
You should be comfortable at Henle level 6 — meaning you can already play level 5–6 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 Allegro Eroico lasts about 5 minutes.
Allegro Eroico 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 1st Piano Sonata by Ana Leira Carnero, Ballade No.2 by York Bowen, Cambrian Ballade No. 2 by Joseph Holbrooke — see the full similar-pieces list on this page.