Just extremely frustrating. You open the battle with a cool image, sure. But it is a maneuver that makes absolutely no sense. What was emphasized in the Battle of the Bastards about being flanked by cavalry? And when the White Walkers finally took the field, that should have been a "oh ****" moment. But, nope. Nothing. Next we see them, is they are statues. I really liked the Arya scenes inside the castle, and feel that could have been expanded on.
I will hand it to them, they created a great illusion of devastation for the main characters. So many characters should be dead, but apparently they have more plot armor than I thought. Sam is the one that bugs me the most. I will admit, I yelled out when Arya came out of the shadows.