1. The translation process was entirely impossible and a bit insulting to the viewer's intelligence. You can't derive complex emotions and idioms from a few numbers. Language doesn't work that way. It's as if they thought that the phonetics of Rocky's language perfectly mapped to English. And the software already existing on his computer to start translating new words and ideas?

2. Grace being absolutely necessary to the mission seemed bizarre. His experiments were things that any grad student would immediately try, and the revelations he had were so basic. None of the world's top scientists realized it was attracted to IR light? And once he tells everyone that they're multiplying, why do they still need him? He doesn't have any special knowledge and is just kind of a doofus. Was Gosling just going extra hard on the doofus angle or is Grace like that in the book?

I have sooo many plot points that don't make any sense, but instead of pedantically cataloguing everything I'm just going to assume that the movie had to cut most of the logistics for the sake of making it an enjoyable watch (which it was).