I'm going to push back against one common thought. I don't think that the problems of the past two seasons are due to time restraints. I think they just used their time poorly. There's no reason why in 15 hours you couldn't come up with a compelling reason why the characters ended up where they ended up. They just didn't do it. Like I've been saying for weeks, if they knew that Daenerys was going to go crazy, then they should have written her differently in the 11 episodes leading up to it. If they wanted Arya to run away, then why was she starting to settle roots at Winterfell right before that? If Jaime was going to relapse, why have him do it as a complete 180 at the tail end of an episode? And so on down the line for pretty much all the characters' arcs.
There was time to move the characters into the places they were going. They just didn't bother to do it until it was time to do it.