Dany's character change was not well developed and far too abrupt. I kind of get why she would torch the city, wanting to rule by fear instead of love, but not really.
Watching the episode last night, I could just keep thinking, really? REALLY? So they want to end with Dany as the mad queen taking after her father, but they just haven't developed that. For years, seasons 1-7 they set her up as the benevolent "Breaker of Chains". Now over the course of what, 10 minutes screen time, she's a crazed lunatic burning women and children? Nah, it doesn't wash.
This could be the reasonalbe ending of the show, but they needed more time, a lot more time, to develop that. This should've been a normal 10 episode season with one more to follow, then they'd have had time to do this right. It just seems rushed now.
GoT season 8 reminds me of the HBO series Rome. Season one was killer. They initially planned to do five seasons, but after the first they only got the green light for one more. So, season two was rushed and lackluster. It's too bad.