First of all, there were too many errors in this book for me to give it a really good rating. I can understand a few errors; I know how easily one can miss an occasional misuse of a word, or omission. But toward the end it seemed there were one or two egregious errors on every page. Sometimes they were so bad I had to re-read paragraphs to try to understand what was intended. There is no excuse for that. It makes me angry because that level of errors is just laziness, and it seriously undermines my enjoyment of the book.
Second, I think the book was too long. I got the feeling the author couldn't really decide what he wanted the story to be about. There were too many plot threads, some of which were dropped early on in the book, some of which seemed to come out of nowhere. And there were some things which really needed more back story. For instance, the two human alliances needed a lot more explanation.
I think some of the character development was lacking too. I liked Tebrey, and I think he and his companion were pretty believable and well developed, as were most of the scientists. But I didn't believe the love story. I suspect that is partly because Ana was one of the least developed characters, and partly because he didn't spend much time on the romance.
It's really a shame, too, because the story had real possibilities. The world building was pretty good, though it had some holes, and the plot was decent, if a little complex. And there seemed to be a lot of potential for future stories.
I haven't decided whether to give any sequels a try.