The Martian is a good example of transparent writing, where the prose gets the job done and doesn't call attention to itself in either a negative or overly positive way.

The Martian might not win any literary awards but writing like this is a much overlooked skill in authors.

Thanks, I'd broadly agree. They are definitely "good enough" and Wier's writing has improved noticeably, but The Martian was a little shaky at times!