It's true that the writing is flawed in many ways. But you are overlooking the things it does well. It's not really the character designs that make it (although they are no doubt a part of it), but the character portrayals. The characters, in their totality, carry the show. In effect, it's a character-driven show, not a plot-driven one. The biggest flaw is that the writing does not let it be entirely character-driven, but attempts and largely fails at plotting.