I like all kinds of books. 
 I generally don't have much of a problem getting into SF that happens to be more about family and interpersonal drama than about space... but I do like to know that this is what I'm getting into. 
 By all accounts, the extended opening felt like a glorious character-driven lead-up to a tight and absorbing journey to Mars. But when the interpersonal stuff took over and most of the page space was devoted to different family members, all of which stayed behind, I had to conclude that this whole book wasn't really about Mars or the journey for the three Astronauts, even though the tale centered on them. It merely had the cool journey be a pivot for deep internal monologs and stream of consciousness. It really could have been set anywhere. It just happened to have space travel as the spice. 
 The plot really isn't that important. 
 The character studies are where this book shines. From issues of being gay to finding a balance in your life or even the ideas of what is art and despair, it does shine. 
 I wonder if this is going to be a new "thing", though. I've been reading title after title lately that is just mainstream topics and exploration with just a tad of science or science fiction. Maybe one dystopia here or one exploration there, but the rest is just a mainstream novel that could have been marketed so easily as another genre. 
 Don't get me wrong. It's fine. But I am quite fond of my science and my science fiction. I'm used to my SF having truly glorious themes and explorations and complicated structures. I'm just not sure what I think about bare-bones and mild A-to-B SF plots becoming a carrier vectors for other genres. 
 Otherwise, the writing is quite good and I otherwise probably wouldn't have had any complaints.