Léo Delibes

I've just listened (for the first time) to Léo Delibes music to Sylvia and Coppélia, and they are wonderful I was reading a Tchaikovsky biography, and he raved about Sylvia, so I decided to check it out, and yeah - it's amazing - melodic, thrilling, beautifully orchestrated, but not cheap or cloying; real melodic and dramatic invention; but when I went to see what else I could find, ...there's not much! He wrote over 22 operas, and only one (!) has been recorded: Lamke - and while his three ballets (the first being La Source) have been recorded (numerous times), the rest of his output is practically 'zero' on recordings. From what I've heard, his works were very popular during their time, but no record label ever invested much in his oeuvre outside the "big four". Why? Why has there not been a concerted effort to preserve his 'other' music? It must be at least as interesting and accomplished; he was highly regarded during his life - even though he dabbled in 'light' operetta in his early years, he moved beyond to more serious topics later on, and wrote a great deal of vocal music, both choral and small ensemble numbers (check out his Hymne de Noel for an unheard Christmas treat.)