A famous Mexican waltz later arranged for piano, often associated with the 'Vals Alejandra' style. It features a sweeping, lyrical melody that is highly idiomatic to the instrument.
Developing a singing tone (cantabile) in the right hand is essential for this melody-dominated work.
Comparable difficulty and character — good candidates for what to learn next.
Alejandra 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 Alejandra lasts about 3 minutes.
Alejandra 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 Für Elise by Ludwig van Beethoven, 'O sole mio by Eduardo Di Capua, Believe Me, If All those Endearing Young Charms by Irish Folk Music — see the full similar-pieces list on this page.