Honestly, I've enjoyed this series. The romance is quite mild but the mystery plots made it entertaining. For a ratio, every one lovebird scene, there two serious plots. 
 For the romance sub-plot, Charles had a bad feeling about the incoming Alpha gathering (Bran's dad, the Marrok aka US alpha-king, wanted to come out to the world about werewolves) in Seattle. He insisted to come at his father's stead with Anna, his Omega, at his side. Although they're newly married, they're still trying to figure things out between them; Charles being antisocial; Anna's intimacy issues and etc. 
 There's a lot of testosterone poisoning-inducing dominance display , vampire-assassins, murders, betrayals and all sorts. It was very lengthy and hardly any fillers. The POV switches between characters and its not really hard to get along with the characters. It does have Underworld feel in it too. 
 Some normal PNR readers might put off with the tendency to quickly end the love scenes and smallish heart to heart moments between characters. If you have short attention span for fictional werewolves politics in this book, the series might be a bore for you.