This work is a set of virtuosic variations based on an operatic air by a master of the guitar writing for piano. It is distinctive for its clear classical structure paired with early Romantic melodic embellishments.
Students must focus on clean finger-articulation in the rapid-fire ornamentation.
Comparable difficulty and character — good candidates for what to learn next.
'The Mysteries Of Isis', Air With Variations (Op. 24) is rated Henle level 3 of 9 — late beginner repertoire, roughly ABRSM grades 4–5. In the RCM system it corresponds to about level 4.
You should be comfortable at Henle level 3 — meaning you can already play level 2–3 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 'The Mysteries Of Isis', Air With Variations (Op. 24) lasts about 6 minutes.
'The Mysteries Of Isis', Air With Variations (Op. 24) 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 'Le songe de J.J. Rousseau', air varié by Matteo Carcassi, 'Under The Moonlight', Song From 'The Paid Carriages' With Variations by Matteo Carcassi, The Entertainer by Scott Joplin — see the full similar-pieces list on this page.