The First Contact scenes were the highlight of the book. I could've read an entire book dedicated to those first days of communication between Grace and Rocky - first contact is fascinating to me, especially in the problem-solving parts of communication. I love the
Cosmic Call project for the same reason. Weir did an excellent job of playing with that and exploring the psychology of a civilization that never needed to "hear light."
Just like with
Martian, the bits on Earth were the weakest. I don't know why Weir puts so many unnecessary characters in his books, but it was even more egregious this time. At least with
The Martian, Earth trying to do problem-solving and communication with Mars was part of the shtick and it worked. But here, Grace is alone in space and Earth can't help. Doing flashbacks was a clever way to show his science homework, but we didn't need to meet
every bit character who invented a new solution. We're never coming back to any of them and it shows. We only got basically 1 scene with every character and it made them feel very flat and archetypal.
Even at the end of the novel, I felt nothing for Ilyukhina and Yao, even though we got hints at the start that Grace was very sad and was fighting back the memories to stay functional. That didn't really go anywhere. Only Stratt was at all interesting to me, and I wanted to focus on Grace & Stratt's relationship the most (of the Earth relationships at least). Doesn't feel like I got a good resolution on that - and the amnesia drug betrayal was interesting but I don't feel like the story did enough with it. Realizing you're a coward who had to be forced into a suicide mission at the
end of that suicide mission is a cool storytelling opportunity. I wish we'd gotten more about that.
Basically, I loved Rocky and always preferred more scenes with "him" than anyone on Earth. Tau Ceti was the emotional core of the story, so just keep us there.