Danaerys is one of my least favorite characters in the books. But, remember, even though the actress is playing her at 18-20, she's only 13-15 in the books, so that's where the majority of her dialog comes from.
Clash of Kings is a great book. I'd rank it #3. But, they gutted Jon Snow's story, made Catelyn weak and destroyed her motivation, and weakened Robb's story as well on the show. Plus, I'm a sucker for San/San (Sansa and Sandor Clegane), so I'm disappointed they cut a scene or two from them as well, and his best line, "Bugger on your Ser."