Per Lasson's Albumblad No.2 is a quintessential example of Norwegian Romantic salon music. It focuses on gentle melodic contours supported by a flowing waltz accompaniment.
Students must master the flexible rhythm to avoid a mechanical sound in the waltz accompaniment.
Comparable difficulty and character — good candidates for what to learn next.
Albumblad 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 Albumblad No.2 lasts about 3 minutes.
Albumblad 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 Andante by Wolfgang Amadeus Mozart, Andante favori by Ludwig van Beethoven, Black Beauty by Duke Ellington — see the full similar-pieces list on this page.