Though less famous than his major sets, this Chopin piece combines the grace of a dance with the introspective quality typical of his middle period. It captures the specific rhythmic nuance of the Polish mazurka.
The primary challenge is the subtle, idiomatic rubato required to make the dance feel authentic.
Comparable difficulty and character — good candidates for what to learn next.
Allegretto and Mazurka 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 Allegretto and Mazurka lasts about 4 minutes.
Allegretto and Mazurka 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 Waltz in C-sharp minor, No. 2 by Frédéric Chopin, Waltz in A minor by Frédéric Chopin, Nocturne in B major, No. 1 by Frédéric Chopin — see the full similar-pieces list on this page.