Though primarily known for guitar works, Sor's piano music carries a similar intimacy and refined texture. This piece is a masterclass in economy of expression, using subtle harmonic shifts to evoke a melancholic, serene mood.
Achieving a warm, singing tone without allowing the left-hand accompaniment to overpower the delicate melody is the main hurdle.
Comparable difficulty and character — good candidates for what to learn next.
Andantino in A major is rated Henle level 3 of 9 — late beginner repertoire, roughly ABRSM grades 4–5. In the RCM system it corresponds to about level 5.
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 Andantino in A major lasts about 3 minutes.
Andantino in A major 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 As in a Rose Jar by Charles Wakefield Cadman, Albumblatt für Frau Betty Schott by Wilhelm Richard Wagner, Berceuse by Rudolf Friml — see the full similar-pieces list on this page.