While I read a prodigious amount of Sci-Fi and Fantasy, my
favourite 'genre' is American & European 'Modernism" - Hemingway, Steinbeck, Faulkner, Schulberg, Mann, Joyce, etc.
Also the Magic Realism of Allende, Cortezar, Marquez - 180 dgrees of difference between the two, but both reflect (interestingly) the societies they sprang from.
I don't think I've read a "serious" book in the last 20 years that compares to any of these authors (maybe Vikram Seth or Brett Easton-Ellis).
I also really like Janet Evanovich.