The characters are well developed and the plot is excellent, but the most amazing thing in this book is probably the sheer thought and research that has been put into the science. It hasn't been just explained away "it's future, we don't get it yet"; instead, everything from armament to space travel is meticulously detailed. I also tremendously liked the feminist vibes I got from this book. I'm not sure if the author meant it like that, but the characters are first and foremost humans, not women or men. They can be geniuses, idiots, starship captains, engineers, and everything else, and their gender doesn't matter. It's so natural in this book it isn't even commented: there's no single line where someone's gender comes as a great shock. 
 Like the science, the battle scenes are also very detailed and gruesome, and I wouldn't recommend this book to anyone who can't stand violence; I've rarely read a book with so much blood and gore. However, the violence fits into the book naturally instead of it seeming like the author deliberately wanted to shock readers and make them feel ill.