William Mason was a prominent American pedagogue whose compositions often blended European Romanticism with American parlor style. This piece serves as a study in harmonic color and phrasing.
Focus on the subtle use of pedal to connect wide-spaced harmonic shifts in the left hand.
Comparable difficulty and character — good candidates for what to learn next.
Ballade No.1 (Op.12) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
Ballade No.1 (Op.12) 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 et barcarole by William Mason, Ballade et barcarole by William Mason, Waltz No. 2 by Dmitri Shostakovich — see the full similar-pieces list on this page.