So as I was reading the Catholic-fiction criteria here just now, this observation of Kreeft's came to mind (though I had to think a while before I remembered where it came from, despite having read it only an hour ago):
Atheism cheapens the world, cheapens life. To see this, just compare atheist fiction with theistic fiction. Belief in God does not squash man; it raises man to a divine image. Heroism grows only in the sunlight of a divine sun. Squash the ceilings down low, and we stoop. In classical Greek drama, in Shakespeare, man is great because he breathes the air of the absolute. In Faulkner, Gide, Sartre, Camus, Beckett, and nine out of ten lesser twentieth-century writers, man is "full of sound and fury, signifying nothing" because he is a cosmic orphan. His universe is man-sized, not God-sized . . . Life in that world is a meaningless flicker of a candle for a few between the cold and barren darkness of two eternal nights. (from Making Sense Out of Suffering
I wonder about Faulkner -- I'm not sure all his work fits this framework which Kreeft proposes. That is, I'm not sure it's all as atheistic in its outlook as The Sound and the Fury. Then again, I'm not sure it's not. But generally I think Kreeft is right, and one dividing line is that between the novel of the hero and the novel of the anti-heroic ant-on-the-surface-of-the-naked -globe-which-is-all-there-is kind of protagonist.
A novel which keeps swimming to the surface of my mind is Willa Cather's O Pioneers. But I think I need more coffee, and more time, before I talk about it. We're supposedly going to a historical re-enactment day at Kings Mountain down the road, but nobody seems to be making gestures in that direction right now . . .