There's a lot of good stuff here but I have to throw Andromeda Strain and World War Z into the pot.
Books
Book reader community.
The Mistborn Trilogy (start with The Final Empire) by Brandon Sanderson is superb.
After that initial trilogy they are a massive struggle, but the first three are well worth reading.
I absolutely agree with your recommendation, but man if they're looking for something short, the mistborn series is the opposite lol
Not really sci-fi, but shirt and very good: Fictions/Ficciones and Labyrinths by Jorge Luis Borges. Also, Invisible Cities by Italo Calvino.
Something not by one of the more well known authors I could recommend are the Indranan War trilogy and Farian War trilogy, by K. B. Wagers
Also, The Frontiers Saga series by Ryk Brown is fantastic, and I think getting close to 40 books by now
Naive Super. Not sci-fi, but a quick enjoyable read. I've read it 4 times now. Its just a fantastic simple book to get back into reading fiction.
Haven’t seen this one mentioned, but The Three-Body Problem by Liu Cixin might work. I don’t believe there’s a lot of first person, but it’s an interesting read.
There are some great suggestions here - I'm also adding to my reading list!
I almost exclusively read sci-fi, and my favourite author is Peter F. Hamilton. He has written some mind-bendingly good space opera, much of it spanning multiple novels.
His best work IMHO is a one-shot, standalone novel called Fallen Dragon. It's got rampant uber-captialism, space marines, geurilla warfare on colony worlds, and aliens. And a very satisfying conclusion that I didn't see coming.
You might try some of Azimovs short stories. For a bit more meat you might try Frederik Pohls Hee Chee saga. Book 1 was great.
Its not scifi, but Thieves Emporium by Max Hernandez.
Read Everworld
@foofiepie continuing with sci-fi definitely check out the Monk & Robot series by Becky Chambers!
“A Psalm For the Wild Built” & “A Prayer For the Crown Shy”
Short & beautiful.
Roadside Picnic. Not too long, but phenomenal overall and told via first person.
John Scalzi's book are an easy read. Its a lightweight Sci fi though.
Old Man's War, and Starter Villain are the two of his books I've read and enjoyed.