Hard to review this book. I think my score would be more a 3.5, but I like to support indie authors, so an extra half.
There's a LOT of exposition. Too much, I think. There are a million POV characters, to the point I lost track of who was who several times. There are so many story threads it's hard to follow, and the entire first 2/3 of the book feels like world building, backstory and in some places, filler. And yet...The story is great, many of the characters are very likeable and as the first book in a trilogy, I would expect the majority of the world building and background is done now, and the next two books will be more like the final third of this one.
And that final third really shines. The writing crisped up, the dialogue too, the action and pacing sped up and yet evened out as well, and all the threads that were not entirely making sense to me earlier in the book, came together into a whole.
Probably the best indie sci-fi I've ever read, I really enjoyed it, and I will be looking out for the rest of the series.(Disclosure: Picked it up as a freebie from the Amazon daily free books)