I don’t think Stan Lee really knew how to write Daredevil. He knew how to conceive the character, and had great ideas and storylines, but the words themselves…Don’t match very well. Stan just isn’t a “dark” guy.
The Mike Murdock concept is actually pretty radical, pretty meta: A blind superhero creates a sighted twin to serve as fake secret identify of the superhero, all so that he can finally date woman who loves Daredevil, Karen Page. It all turns out wrong, of course, so he has to kill his twin.
But then, when that’s over, who will be Daredevil?