The fourth Cambrian Ballade is perhaps the most harmonically complex of the set, featuring dense textures and subtle polyrhythmic passages. It creates a deeply reflective and dark mood that showcases Holbrooke's idiosyncratic orchestration-like writing for piano.
The main technical challenge involves articulating complex polyrhythms while maintaining a clear melodic line.
Comparable difficulty and character — good candidates for what to learn next.
Cambrian Ballade No.4 (Op.104) is rated Henle level 7 of 9 — late advanced repertoire, roughly ABRSM grade 8 and above. In the RCM system it corresponds to about level 10.
You should be comfortable at Henle level 7 — meaning you can already play level 6–7 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 Cambrian Ballade No.4 (Op.104) lasts about 9 minutes.
Cambrian Ballade No.4 (Op.104) 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 Cambrian Ballade No.1 by Joseph Holbrooke, Cambrian Ballade No. 1 by Joseph Holbrooke, Cambrian Ballade No. 3 by Joseph Holbrooke — see the full similar-pieces list on this page.