Run this formula for all variations of the D and D "Create a nonsensical plotline " meeting.
-Characters who are foreign, either in location or familiarity need to be developed. If they are not developed well, they need to be likeable. If they are not likeable, they need to be directly linked in proximity with characters who are likeable.
Without Sansa, even though her motivations are at best unclear at this point, there is no reason to focus a storyline on Winterfell except that Stannis is attacking it. Ramsay is not a fun character to watch when he's not torturing a character we care about. If the season shows little of Roose/Ramsay and only shows Stannis' difficulties, it is assumed that the Boltons are either unaware or unprepared for an attack. Without the Manderlys, it is assumed that the Boltons have no concept of northern opposition to their cause.
Using show logic, you have to assume that Ramsay would flay Wyman Manderly just as readily as he flayed any other disobedient lord. Aren't you glad he isn't in the show?
I agree though that they need to give Sansa something to do (anything) and fast.
As for Dorne, this has just been horrible all around. I can't excuse it other than to say they had an inexperienced crew with miscast actresses. However, this plot does adhere to the "We need a familiar face in a strange, foreign land." Even if they had just had King Dorann and none of the sand snakes, they still need someone we know to interact with the people we don't. Otherwise they have to build a whole new character.
