By your explanation, I'm 100% sure that the original has been weak story-wise. Dormer is such bad guy in what you explained. I'm not interested in watching the original unless its other elements are attractive. When I first watched Nolan's Insomnia I considered it my least favorite of Nolan movies, but last night re-watched it and paid better attention. Now I consider it among other Nolan's masterpieces and I'm glad that by this Nolan established himself as a powerful guy in cinema by remaking a movie which some directors don't dare to touch.