I like this even more after The Martian
The Martian is a great movie, with a great cast, a great director, wonderful special effects, but it has the same major flaw the book has: poor character development. In the end the main character is the exact same person he was when the movie started. Yes, we can come up with excuses like "NASA wants mentally resilient and spirited people as astronauts", but that's not what storytelling is about.
The Last Push isn't a great movie, it's barely a movie at all, but it focuses completely on the one thing that was missing from The Martian: how an astronaut in such a situation would feel. Despite all the money and talent poured into The Martian, no scene made me feel his isolation, loneliness and despair like some scenes in The Last Push did.