I thought the episode was fantastic. Best of the year by far.
I understand some of the criticism I have seen, but not others.
Some of the criticism of how Dany turned out seems like simple "not getting their way". This is almost certainly the way it was always going to end. The whole thing fits right in with the vision Dany had in, what, season 2? And also the vision that Bran had, that featured some of the same images. Dany has been losing it, piece by piece, for years. I never believed that she would just accomplish her goal of winning the throne and being a benevolent ruler happily ever after, and anyone that did think that hasn't been watching the same show that I have. Expectations of happy endings have been subverted since the first season (or even the first episode).
I also don't understand the criticism of how "Jaime's arc ended". He didn't have an arc. He didn't go from evil to good. He was always evil. He was always good. He was one of the most complex figures on the show, and like so many others, had his share of faults. He was always honorable and upstanding in most ways, except for the big blind spot in his vision that was Cersei. Around her, he couldn't help himself, but away from her, his more positive traits always came through. But she was the black hole from whose orbit he was incapable of extricating himself.
The Clegane battle was fantastic. And I'm glad that Arya got away. Hopefully she has a moderately happy ending (or at least a purposeful one, which may be the best that this world can give her).
Also, how Dany dealt with the scorpions actually made perfect sense. The weakness was that they are so huge that they are not easily maneuverable and take a while to reload, weaknesses that are mitigated when firing at a target caught unawares (as in the last episode). Dany attacked the fleet from above with the sun behind her, so they couldn't get clear shots, which enabled her to take them out fairly quickly. Likewise, the when she got to the city, they weren't pointed in the right directions, enabling her to take them out as well.