I'm kind of surprised by you're not liking the martian. Have you read the book? I read the book (but haven't seen the movie yet) and its definitely on of the harder sci-fi books I've ever read. With the exception of the flexibility of space suits and problems with a benzene reaction, the physics, chemistry and biology are pretty good. Maybe this didn't translate to the movie as well (which might have been nigh impossible) or was glossed over in an unsatisfactory way.

And as for the astronauts, I've actually heard that astronauts find the attitudes reflected exactly right. All from a guy who didn't know any.