We really did need more stuff with the Lords of the North, some exploration of the after effects the Red Wedding had on everyone, more "The North Remembers" storyline. In the books it was a massive deal that Ramsay Bolton had a daughter of Ned Stark for a bride. Every lord above the Neck wanted to murder Ramsay for what the way he was desecrating the Stark legacy, and it was all from a place of loyalty to Ned and Robb's memory. It's cathartic to show that in the North at least, people still recognize and love the goodness of the Starks. We got none of that.