These come to mind:
Gioacchino Rossini (oh my GAWD...how could anyone leave him off? At least as good as Donizetti in the early 19th Century Italian School)
Luigi Cherubini (pathetically underappreciated)
Domenico Cimarosa (ditto)
At this juncture, I need to inject some
humour:
Rossini, in addition to being a great composer, was also a gourmet chef and a gourmand (a person who loves to eat), as well as being a very funny/witty man. Here are some quotes attributed to Rossini:
"In my whole adult life, I have only wept twice: once when I heard Paganini play the violin, and again when I saw a truffled turkey fall into the water a boating party."
"You know, this fellow Wagner has some wonderful moments, but some incredibly dull quarters of an hour." (Rossini lived long enough to hear some of Wanger's operas, and many of us echo his sentiments)
Trivia: Rossini (in his capacity as gourmet chef) is reputed to have created the classic dish "Tournedos Rossini" (tenderloin of beef with truffles and
pate de foie gras on toast rounds...it's delicious).
Another humourous quote, this time from Donizetti
about Rossini:
When told that Rossini had written an entire opera in 10 days, Donizetti replied dryly: "That bastard Rossini always was a lazy son of a bitch."