Norman O'Neill was a British composer best known for his incidental music, and his solo piano works often display a charming, late-Romantic sensibility. This piece is a salon-style miniature that focuses on melodic grace and subtle phrasing.
The student must balance the lyrical melody against a gentle accompaniment without over-pedaling.
Comparable difficulty and character — good candidates for what to learn next.
All Fours is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
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 All Fours lasts about 3 minutes.
All Fours 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 Andante by Wolfgang Amadeus Mozart, Andante favori by Ludwig van Beethoven, Black Beauty by Duke Ellington — see the full similar-pieces list on this page.