Nah I knew the big battle was the 3rd episode so it stood to reason this would be similar to the first one. This one did have its moments but a lot of it I found to be pointless filler and maybe a bit too much of fan service (Sansa and Theon and even Arya to a degree though that at least made a bit more sense to show more of a human side to her).
I was left feeling like they could have combined episodes 1 and 2 in less than 1.5 hours and then have more time for the big battles to come.
I'm afraid your theory is right about the Night King. They didn't show him at the end of the episode last night! I hope we are wrong as I'd like to see the Night King and Co dealt with here and then the remainder being King's Landing, but that may not play out that way.
The highlight of the episode to me was Jaime and Brienne. Which of course means 1 or both die next week