They made Darnell just as big, if not bigger, a tool as Earl.
There was nothing loveable about Joy, in fact if there was a stereotype in the show it was her being nothing more than plain trailer park trash and taking advantage of literally anyone that came too close to her. Yet, Earl felt compelled to try and right his wrongs to her even after she lied him into a marriage and then cheated on him. Darnell is shown to actually love Joy despite the fact that he had the character and education to know what she was.
That being said, it was an entertaining show. My favorite part was the Randy/Catalina angle.