Richard Stöhr's Suite displays a complex, late-Romantic to early-Modern harmonic language with significant technical demands. It is distinctive for its dense textures and varied character shifts across the suite's movements.
The player must manage wide-span chords and complex voicing throughout the suite while maintaining stamina.
Comparable difficulty and character — good candidates for what to learn next.
Ballet Suite for Piano (Op. 112) 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 Ballet Suite for Piano (Op. 112) lasts about 12 minutes.
Ballet Suite for Piano (Op. 112) 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 Bourrée fantasque by Emmanuel Chabrier, Variations and Fugue on a Theme by Handel by Johannes Brahms, Wanderer Fantasy in C major by Franz Schubert — see the full similar-pieces list on this page.