Despite the first book winning the 2021 SPSFC (admittedly, a much less well-known competition than the SPFBO), I almost never see the Primaterre series by S.A. Tholin mentioned. They are doorstoppers, but very well paced, imo: I inhaled the first two books. If you like space opera that manages to avoid a lot of plot tropes, give the series a try!
(Sidenote: if you’re put off by the “cosmic horror” label on the first book, I recall there being a couple of mildly gory scenes, but it’s mostly in the realm of “unfathomably alien” rather than trying to scare.)
I saw the movie first, then read the book after hearing it was different/maybe better, since aside from the bear, I found the movie fairly whelming. I ended up really enjoying the book, particularly the dream-like style. Authority, however, I found… really slow. I was intrigued by the premise, and the reveals were interesting, but the pacing was just glacial, imo, and it did away with what I’d liked about Annihilation. I did start Acceptance afterward, but was sort of over it at that point, and never finished it.