What is the best tasting food? What is the best photograph? ....
You may be able to create a partial order of some sort, but I believe value is in the eye of the beholder.
I think War and Peace is drivel, same thing with Grapes of Wrath and Great Gatsby.
But I liked Death of a Salesman and Fathers and Sons and My Antonia.
I thought To Kill a Mocking Bird was not much better than the fiction I was reading on my own.