the sound of Wicked isn't really due to Schwartz alone. It sounds like you are interested in big, dramatic orchestrations. In that case:
Alan Boublil - Les Mis, Miss Saigon, Martin Guerre, etc.
Webber - specifically Evita, Sunset Blvd.,
Lawrence O'keefe - Composer of "Legally Blonde", though "Bat Boy" is more similar to that style than Blonde is. also, look for a recording of "3hree" his is the first show- "The Mice"- has some really nice gems in it.
hope that helps
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