What Charakters dissapoint you in the Books related to the Plot and the Story?
For me it was Balon Greyjoy, a very interesting Figure, who just had a minor Role and die much too soon (also he was way better portraited in the TV-Series)
The Death of Tywin was a Shock, but also a bad Move, since he was a big Force in the World of SOIAF and leave a big hole in the Story.
The Part of the Others is very, very slow, will they ever overcome the Wall? I dont think they are such a great Danger for the Kingdom, like they should be...but maybe this will be fixed in the next book.