i think they could do cool things with the character, similar to what gerstmann said, by going the "what happens when you stop being in on the joke and become the joke?" route
like, in his mind, duke is walking around with money falling out of his ass, everyone adores him, and all the ladies giggle while biting their lower lips at all his sexual innuendo - then you'd get brief flashes of reality where he's some brokeass highway worker, everyone is repulsed by his attitude and laughs at his ridiculous clothing, and instead of "what're you doing later besides ME, stud?" they're really saying "go fuck yourself, asshole."