If I'm interpreting you right, it sounds like your trying to defend many of the over-the-top aspects of the film because it's a ghost story. While this is one of my favorite Christmas movies, I think the film was far to over-the-top at times. I loved the designs of the ghosts (the spirit of the future as a shadow was genius), and I loved the imagery of the movie. But I think every ghost story needs a bit of subtlety. I get tired of the old cliche of monsters jumping out and going, "OOGA BOOGA BOOGA!!!!!!!!!!!!!" It gets really old really fast, and can actually distract from the story the filmmakers are trying to tell. The ghosts in A Christmas Carol aren't supposed to be scary because they jump around and screech and howl and chase people. They're supposed to be scary because they represent aspects of Scrooge's life that he fears. And you have to admit that at times the movie felt like comedy with some of the stuff they did with the ghosts, such as Marley's ghost suddenly getting a loose jaw and talking funny (I laugh everytime). It felt inconsistent with the rest of the scene. I think the movie needed to be more subtle with ghosts. The most important thing with any horror or thriller story is that you have to try to intrigue the audience by feeding on their own fears. Just having a monster or ghost jumping around and screaming just gets really old really fast. It's been used a million times before, and the most it does it make the audience jump, if at all. That's not what horror or thriller should be.
"I shall take the heart, for brains do not make one happy, and happiness is the best thing in the world."