"Off to be the wizard" is pretty light and fun. "John dies at the end" was fun, not really sci-fi, more buffy the vampire slayer esque. "Existence" by David Brin made me want to puke it had so many good ideas. A tiny bit dated, but very smart. "The Martian" I expect you've read it. Good romp, easy to read. Reminded me of a Michael Crichton. "World War Z" was good.
Also recommended in this reply