After re-watching this series
Spoilers below
And acquainting myself with the back-story of the previous few generations before the generation in the main story, I got so much more out of it. Kind of like watching the Godfather series the 2d/3rd time.
In that context, I now feel the final season, including the climactic battle (if you will) in Kings Landing makes a lot more sense. The Targaryans were an unstable family, with generations of incest behind them, Dany's one brother was a cunt, her older brother seemed decent, but her father, the 'mad kink', was batshit crazy, saying 'burn them all', doing a lot of slaughtering. A bit of foreshadowing. Also the saying, "having a Targaryan is like flipping a coin."
We saw how isolated Dany was - no family to speak of, only a very few trusted courtiers. She was, understandably, convinced of her destiny, but became more isolated and more tyrannical as the series progressed. Losing her most intimate woman friend seems to have put her over the edge - remember that all of her Dothraki court were slaughtered earlier.
The first time I saw the series, not having the context of all this, thought her 'transformation' was unrealistic. Upon second viewing, much less so. I think a lot of the negative reception the end of the series got was from viewers like me, not totally tuned into the story, the history behind.