Project Hail Mary is light reading sci-fi. Which is fine, I enjoyed it, but if you are looking for something meatier, covering broader themes and character development, here's some other recent stuff (there's a lot of old stuff covered already in other comments):

Stories of Your Life and Others; Exhalation (Ted Chiang) - both are short story collections vs novels, though

Dissolution (Nicholas Binge)

Too Like the Lightning (Ada Palmer) and sequels (wordy, philosophical, interesting future society)

Tell Me an Ending (Jo Harkin) - more near-future and grounded

Void Star (Zachary Mason)