GavestonPS said: "STREET SCENE (Elmer Rice, Langston Hughes, Kurt Weill) is "obscure" to most theatergoers. It ran for a couple of months in 1947 and hasn't had a major revival since. I wouldn't even know it if Equity Library Theater hadn't done a brilliant production off-Broadway in the late 1970s.
HOWEVER, it is done in opera houses and has had major recordings from both the English and Scottish National Operas. It was shown on PBS and is currently available at BroadwayHD in a production but the Madrid Royal Opera. (BTW, the English production gave us a very young Catherine Zeta-Jones in the "dancer" role.)
So "obscure" as a musical play, but not so obscure as an opera. (In fact, I have trouble choosing between STREET SCENE and PORGY AND BESS as my favorite opera.)
The same could be said of most of Weill's work (RISE AND FALL OF THE CITY OF MAHAGONY, SEPTEMBER SONG, even ONE TOUCH OF VENUS), and yet he is considered, if not the equal of Porter, Rodgers, Berlin and Kern, then at least on the second tier of the Golden Age. Only his THREEPENNY OPERA can be said to be done often (and even so I think it's more of a critical fave than a popular work)."
I agree with Gavestone. I think most of Weill's American shows could be deemed “obscure”, seeing as almost none of them have been produced on Broadway for decades and fewer young theater goers are exposed to them today.
I do believe Kurt Weill is up there with Porter, Rodgers, Berlin and Kern as the best composers of Broadway’s Golden Age, as most people will agree, I'm sure.
Adding to your point about Street Scene not being obscure as an opera, I also get the impression that his German scores (especially the ones wrote in collaboration with Brecht) are considered by some (mostly classical music enthusiasts) to be more “high brow” than his Broadway scores, and thus are performed more often in opera houses and concert halls around the world. As is the case with Threepenny Opera or Mahagonny, as opposed to Lost in the Stars or Love Life.