I would recommend the Red Rising series by Pierce Brown. Every book takes place on a different planet with an amazing amount of character building and detail in the plot.
Books
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Did you finish book 5? That one was a slog for me, and I enjoyed most of the rest (even if book 3 showed much of the strain of finishing the first trilogy, I never felt the pacing slip as much).
I think The Expanse is a pretty obvious recommendation.
I also really like the Remembrance of Earth's Past books by Cixin Liu, but I'm not sure I'd call that a Space Opera. It's a series, yes, but it is very unlike other long-form space operas.
I've heard the Expanse books are great, I watched the Amazon series already. Are the books even better?
I'm seconding the other guy that the books are even better! Plus they go past the point of the show so you'll be able to get more out of the world.
The Honor Harrington series is great for epic space opera.
The Bobiverse is really good too, though less... grandiose? It felt more personal to me.
The Well of Souls serie(s) are great.
For less opera and more funny the Phule books by Robert Aspirin are good.