I have to say, Claudia Gray's novel Bloodline is one of the few Star Wars books worthy of the name "novel". I thoroughly enjoyed it. It does a great job of setting up the backstory for The Force Awakens, the movie makes a lot more sense to me now. I don't know how much of the novel was a retrofit, but it certainly feels seamless, and if it was all planned out, it raises my opinion of the Star Wars story group significantly. If this is where we're going in the future, my misgivings are somewhat assuaged.
Kylo Ren was especially mysterious to me, his childish behaviour in the movie made no sense. Kylo makes no appearance in the novel, but there are hints that some of the events and "revealed secrets" in the novel must have had a huge impact.
The characters and their motivations are well fleshed out and, unusual for Star Wars literature, each character has their own voice. She captures Leia and Han to a T, doing a great job of diving into their emotions and how their past still affects them.
There is a lot of politics in the book (which I appreciate), but plenty of action as well. But it's the kind of action I like: short, to the point, exciting, and not overdone. If you're looking for lists of X-Wing parts, or 5 pages of description for 3 seconds of action, seek elsewhere.
I hope they continue to include Ms Gray in their author lineup, right now she's the best they have.