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.
I have to admit that I’ve never really gotten into other books by Frank Herbert. I’ve tried Messiah and a few of his short stories but nothing came close to Dune. I haven’t tried the ‘WorShip’ trilogy yet (which is the same as The Pandora Sequence I’m guessing?.. I can’t find anything with that name tbh)
The Annihilation / Southern Reach sequels were short enough books that I figured I might as well read them despite some people not liking them. They’re definitely different from the space related stuff I normally pick up, but I’m glad I read them.
I thought they were good! They both made me not want to put them down and kept weaving the horror and mystery together, closed out some of the loose ends and answered questions, but also opened a lot of new cans of worms.