I think Brian Cox would be great as Wireman.
As far as movies from novels go, I think they mostly suck too (ever notice the movies from the books you haven't read are better?). My thinking is a little different than most people though. I think the filmaker gets in trouble when he tries to stay too faithful to the book. You just can't take a huge book and make a 2 hour movie out of it. Film is a completely different art form than a novel so the filmmaker should make the best movie he can from parts of the story he can use. Even though Stephen King will disagree with me, I think Stanley Kubrick's movie is a great movie and a visual masterpiece. It is not the novel but it's a great film and nothing about the novel has changed, you can still read it anytime you want. Kubrick just used the novel as a framework and then condensed and changed the novel to make the best movie he could. The Shining is a great novel and a great movie. Movies don't have to be exact replicas of the novel.