Not just a pretty adagio.
His piano works are solid 'American'-flavour modernism with plenty of melody. [The piano concerto I have known and enjoyed for some time although it is very astringent in the outer movements, to balance a better-than-pretty Adagio...] The Sonata in Eb minor is a masterpiece (especially the fugue finale) and unfortunately, too fiendish for me. But I am definitely going to learn the four Excursions, Op. 20. Number one is is a jaunty, jazzy promenade - almost metallic. Number two is an odd drunken blues. Number three is beautiful - but involves playing 7 against 8, 7 against nine, six against 3-and-a-half, and all manner of compromises. Good thing it's slow and relaxed. The fanfare finale is a meditation... on acid - very sparing with its notes, it alternates F major and Bb major chords with increasing complexity and violence.
The late Ballade, Op. 46, is a joy to play - sounds meaty, mature and hard, but is not too tricky! I feel a programming with Chopin and Brahms Ballades coming on... Meanwhile, the Nocturne, Op. 33, in homage to John Field, is a fantastical world of diatonic harmony and weirdness. A severely excellent work.