American Classical Composer Suggestions

There are a lot of Americans on this subreddit. You will be able to help me. My knowledge of American composers (and their works) is limited to the following names:

Charles Ives Samuel Barber Aaron Copland ​Georges Gerschwin (rather symphonic jazz but I like it) John Cage ​Philip Glass ​Steve Reich Bernard Herrmann Leonard Bernstein John Williams ...

Do you have any suggestions for me or any major American works that you absolutely must know? Thank you so much !