If you don't read the blog called "Prufrock" at The American Conservative, you probably should. It's an always-interesting compendium of mostly literary and general cultural stuff. Monday's post included a list of "recommendations of favorite minor novels." There are dozens of them, of which I've read seven. Many I'd never heard of. A few I think I may have read decades ago. Of course there's no arguing with anyone's designation of a favorite, but there are many possibilities for arguing with "minor." I'm thinking there of promotions from minor to major, but I suppose one might argue that this or that book doesn't even rise to the level of minor.
For my part, of the seven I've (definitely) read, the only one for which I'd argue "major" is Robert Penn Warren's All the King's Men. Some are questionable, but that's the only one that would cause me just to shrug and feel sorry for anyone who disagrees.
There's one on the list I'd recommend strongly to Catholics: J.F. Powers's Morte d'Urban. Especially Catholics who've worked for small Catholic liberal arts colleges.