That's the trouble I have. NBC should be working to market "developing stars" oh what a shocking concept I know. This is the way that actors become stars in the first place. You have to promote and market them. Don't be ashamed the show is a cult hit...embrace tht factor and appeal to those fans then expand to create a higher profile. "The Big Bang Theory" didn't really have mega stars and look at it's popularity. Ed O'Neil and Julie Bowen are the only actors I knew from "Modern Family" and that show has made stars out of the rest of the cast. Look at Melissa McCarthy now...she was a supporting character on "Gilmore Girls" now she's an Emmy winner and writing her own scripts! Also saying "Community" has no big stars is missing the fact that it co-stars one of the biggest comedic actors of all time in Chevy Chase. This is how I first knew about the series in the first place and thought this would be how NBC would market it as Chevy Chase's new quirky comedy show.
Sorry end of passionate rant
Modern Family and The Big Bang Theory are also BROAD comedies. Appealing to a broad audience. It's not just the marketing that is a factor.
Community practically changes it's format every week. I love it, but how do you build on that? Big Bang week in and week out is the same (don't get me wrong, I love it.) And Modern Family always starts out wacky and then ends with a heart felt moment into the camera. (don't get me wrong, I love it)
You can't compare Community to the Big Bang Theory or Modern Family. Very different types of comedy. Compare them more to Arrested Development and Party Down.
It's not just about marketing, it's about content as well.