THE Most important character is Friedrich

In order of importantance starting from the most to the lest is:
1.Friedrich
2.The Narrator
3.The Narrator's Family
4.Friedrich's Family
5.Herr Resch

The other characters are not important and are just to add more contents to the books.
I think Friedrich is the most important character as he represents the Jews and most of the troubles happened on him. The story seems to revolve around him and the narrator's point of veiw. Without Frieddrich, most of the action in the book would be gone and it would no longer be a good read.