Frank Herberts ‘WorShip’ saga is one of my personal favorites after Dune. Although the first book in the series, ‘Destination: Void’ is a hard slow burn.
All the 4 books can be read as individuel stories, but just give a “bigger picture” if read as a series.
There’s also something to be said about some of the more ‘Classic’ Sci-Fi books, like: ‘Starship Troopers’, Do Androids Dream…’ and ‘2001’.
‘Annihilation’ is another really good book. I haven’t read the sequels yet, so I can’t speak on those.
‘The Void’ trilogy by Peter F. Hamilton is another series that might interest you. It’s sci-fi with a hard ‘S’ if remember correctly.