Hi jinfiesto,
I actually have mixed feelings about Mendelssohn. I've posted many of Mendelssohn's Songs here--but not because I'm crazy about his compositions, although I believe I play them fairly well. I learned them (a self initiative) and added them to my repertoire more as a duty to be a "well rounded" pianist. My sense is that Chopin, Liszt and Schumann revolutionized music for piano and created the Golden Age of the Romantic Piano. Brahms and Mendelssohn are considered to have been Romantic composers too, of course, but Brahms, although he admittedly did some daring things, was still rooted in Classicism. Mendelssohn went beyond Brahms and was actually the activist representative of Classicism in his own time, although he put a Romantic tinge on it. His revival of J. S. Bach (although Baroque era) and his own Preludes and Fugues is an example of his looking back to the past for inspiration.
Also, unlike his peers, Mendelssohn was well off and never had to struggle financially to become established. Aside from the death of Fanny, his sister, he didn't experience much tragedy in his life either. Thus, that sense of tragedy that so moved the other composers is not really infused into his composing--it's not palpable. His themes are nearly always upbeat. His music is orderly and many melodies, harmonies and cadences are truly banal or shallow. Some of his piano pieces like the Fantasies remind me of high velocity spinning pinwheels on the 4th of July. But once they end, somehow they are not too memorable. I think others experience that also.
Very tellingly, Mendelssohn well knew his own limitations in writing piano music. When his publishers would request new pieces, he actually agonized over it and dreaded it, as he knew it was definitely not his best genre--he was much more successful as a symphonic composer. So in short, he was not a Chopin or a Liszt. I believe that's why he's not well represented on this forum--his music is probably deemed less complex, interesting, or deep in emotional content, so is not performed as frequently as that of the other Romantics.
But we should remember too that Anton Rubinstein considered the Songs without Words as the very best test of a pianist's mettle. When he would audition a new student, he did not want to hear bravura pieces; rather he wanted to hear a couple of the Songs in order to judge musicality and musicianship. Nevertheless, if I had to guess, I would envision that decades from now Mendelssohn's piano output would likely go the way of the piano works of Carl Maria von Weber. That would be a bad outcome. For that reason, although Mendelssohn might not have been the most dynamic of the Romantics, I think we should all include him in our repertoires to better appreciate what he did accomplish and to share it with others.
Topic: Mendelssohn-Lieder Ohne Worte Op67 No2