This is a characteristic set of variations on a popular Scottish folk tune by a prominent student of Haydn. It showcases the charming, light textures typical of the late Classical transition to Romanticism.
Maintaining a steady pulse throughout the varying rhythmic subdivisions is essential.
Comparable difficulty and character — good candidates for what to learn next.
'The Old Highland Laddie' with Variations (Op.105 No.2) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 5.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 Old Highland Laddie' with Variations (Op.105 No.2) lasts about 8 minutes.
'The Old Highland Laddie' with Variations (Op.105 No.2) 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 'La Sentinelle' with Variations by Ferdinand Ries, Piano Sonata No. 16 in C major by Wolfgang Amadeus Mozart, Maple Leaf Rag by Scott Joplin — see the full similar-pieces list on this page.