When the comedy club circuit came into existence in the early 80's, stand-up comedy unfortunately became standardized: the shorter and/or dumber the joke the better (to appeal to drunks and general audiences). However, in the three decades BEFORE comedy club circuits a lot of comedy was performed in coffeehouses for attentive literate audiences. Steve Martin (most popular comic of his day) was recording in coffeehouses as late as the 70’s, in his heyday. Thankfully a lot of these pre-80's voices are preserved on album/cd.
A lot the guys in the 50's, 60's and 70's were doing bits without a lot of thought as to how long, challenging or quirky the bits were. The book Seriously Funny describes some of the comic innovators of the 50's and 60's as coffeehouse performers. They essentially played for relatively small audiences and then released albums of their work to make themselves known.
It was the comedy club boom of the 80's that made comedy dumb and made short-form Seinfeldian comedy the rule, but that doesn’t have to be the end of the story.
If you're looking for recent comedy that flys in the face of the shorter-is-better/dumber-is-better rule of club comedy, you might check out Bill Hicks. Bill Hicks played in comedy clubs but hated them. Hack Denis Leary stole a number of Bill Hicks' bits, so if you're familiar with Leary, you already have some feel for the political rants of Hicks. And you can always return to the work of the "coffeehouse comics" of the 50's and 60's: Bob Newhart, Woody Allen, Lenny Bruce, etc.
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