Henri Rosellen was a prolific French pianist and composer known for his salon-style works. This Ballade displays the typical lyrical and sentimental character associated with the mid-19th-century French Romantic tradition.
The primary challenge is maintaining a singing melody line against fluid arpeggiated accompaniment.
Comparable difficulty and character — good candidates for what to learn next.
Ballade is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 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.
A typical performance of Ballade lasts about 4 minutes.
Ballade 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 by Hugo Wehrle, Ballade No.1 by Victor Sinadinoski, Ballad for the unsung heroes by Maurice Verheul — see the full similar-pieces list on this page.