Perhaps at root it can be said that Faulkner is a significant writer in the US tradition of Modernist literature, the movement which from the late 19th century thru the 1940s considered ways to reflect things like the splintering of consensus in western societies, the effect of mechanisation and mass media, the discovery of the subconscious and the infinite variety of our internal mental lives by experimenting with new ways of story telling. Multiple points of view, non-linear narratives, unreliable narration, experiments with form and language, with grammar, punctuation, type etc etc were used by poets and novelists in various ways. Faulkner has received a lot of (valid) criticism recently for some of his views and his novels might seem dated, but at the last they are still part of the Modernist project and given a place among 'classics' for that reason. Doesn’t mean anyone has to actually like them of course (or even read them) but, if only for reasons of literary history, they are important.

I had never heard of Comyns discovered this book entirely by accident and absolutely loved it! Like you I can’t believe how uncelebrated it is. Published in 1959 but it sort of reminds me of Angela Carter with its realism with a gothic tinge (which I mean as VERY high praise!). I have found a couple of her other novels since but TBH wasn’t struck by them.

Before the Romantic period of the 19th century much serious’ (as opposed to comic) opera was inspired by classical mythology. There are several works inspired by the myth of Orpheus and Eurydice, for example.

Totally agree with dragon blues comment, it’s definitely affected me in recent years and I had to make myself get back into long form reading. Sounds obvious, but why not start with short stories? The best can be really satisfying as fiction and be thought provoking too. No idea what you like, but the short stories of Irish writer William Trevor are rightly famous for being perfectly formed little gems.