Come to think of it, late-period Henry James is an excellent example of another English-language writer (of the generation before Lovecraft) who uses a very affected, involved, ornate style, but towards very different ends and with a very different effect on the reader (bracketing out for a moment
The Turn of the Screw, which actually is proto-Lovecraft in a lot of ways). Antonio would definitely like him better, as he’s generally more interested in describing psychological states.
ETA: Although in terms of subject matter and tone Lovecraft is obviously more comparable to the earlier Romantic and Gothic writers whom James is riffing on in
The Turn of the Screw and, elsewhere in his body of work, moving away from as part of his realist project. (Careful use of point of view, however, is another trick common to James and Lovecraft.)
The non-Lovecraft piece of writing that reminds me the most of Lovecraft, actually, is
this genuinely delightful bit of homoerotic Symbolist pastiche by the Japanese painter Murayama Kaita. As the title of the book in which the translation appears indicates, this sort of writing is to be understood as a type of Modernism--a classification which Lovecraft himself would have loathed--even though its subject matter and manner of presenting 'reality' is very different from that which we find in the more respectable, canonical Modernist texts such as
Ulysses ('a heap of dung, crawling with worms, photographed by a cinema apparatus through a microscope').
This kind of 'mapping' of physical objects and spaces is extremely, extremely common in sci-fi/fantasy/horror literature of the old school; it shows up also in Tolkien, in a more restrained and statelier prose style and in the service of a very different worldview, and in somebody like Asimov often to the
exclusion of meaningful characterization, and sometimes to the exclusion of dialogue and plot as well! This tendency is modified somewhat in 'New Wave' writers like Le Guin and Moorcock (both of whom I have problems with, for different reasons, although they have more literary control and thus possibly more objective merit than the old guard), but never entirely disappears, possibly because the nature of the genres means that certain things
have to be given fairly detailed physical or technical descriptions as an aid to the reader's understanding. (I'm not going to get into what Mervyn Peake's project is because it's been a long time since I've read
Gormenghast and I'm sure it would take ages for me to refamiliarize myself with it enough.)