I haven't read much Dickens (yes I know it is sad), but I do know this. When he wrote Oliver Twist he wrote it as a very sad story, but also funny. Oliver Twist is about how ridiculous people were back then and how terrible they treated children like Oliver. But in a crazy way he made it funny. You would think that a story like that would only be dark and miserable, but he put a little humor in it.
I think what I am trying to say is that other authors would focus on the bad and only in the bad. Charles Dickens managed to crate a light in the darkness.