Denza was a master of the Italian song style, and his piano works translate this dramatic flair to the keyboard. This piece utilizes shifting dynamics to build towards a climactic middle section.
The challenge lies in managing the dramatic-contrast between the soft and loud passages.
Comparable difficulty and character — good candidates for what to learn next.
'Ncore! is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 5.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 'Ncore! lasts about 4 minutes.
'Ncore! 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 'O surdato 'nnammurato by Enrico Cannio, Allegro in A major by Carl Philipp Emanuel Bach, Canto del esclavo by Nicolás Ruiz Espadero — see the full similar-pieces list on this page.