My problem is with him going to Dorne. His trip there serves no point expect cersei's. and you shouldn't have to sacrifice 1 character plus a nation just for cersei. It's pretty much implied that cersei was doing down since the beginning.
Actually the purple wedding was the big event last season and was only a few episodes in.
Writers love personal attachment. Walking Dead is a big example of this. Eventually you know some of those beloved characters will die and they have died. They want you upset because for some odd reason, even after being mad at a event, we still come back and watch it to learn more. This is exactly what they continue to do.
And i'll even say this, that scene in the book I could really see happening. in the books Stannis is a son of a b**ch who only wants to be on the throne and doesn't care how he gets there, something completely different from the series.