For the whole first seven seasons I wanted her to be queen. I wanted her dragons to roast Joffrey alive, and later Cersei once she was queen, but I was sure she wouldn't kill Tommen. I was worried about what would happen to Tyrion, until he joined her side, him being blamed for Joffrey's death actually seemed to work out.
The one thing I kinda disliked about Season 8 was making her the final villain. She'd often be merciless to her enemies, sure, but this is a world where there are a lot of really bad people who can do some really bad things until someone stands up to them, where people in the Night's Watch get beheaded for desertion or insubordination, and many of Dany's enemies did far worse, and I agreed with just about everything she did in Seasons 1-7, including burning Randyll and Dickon. She gave them a choice and they chose to die, and it wouldn't be good if her enemies thought she was weak like Tommen was. (I kinda expected Dickon to live though, he didn't seem as bad as Randyll)
In Season 7, she flat-out refused to do what she did in The Bells, showing she hadn't become the Mad Queen yet. It was the poor reception to her arrival and the deaths of Rhaegal and Missandei that drove her over the edge.
Though she did seem quite ambitious from the start, absolutely wanting the Iron Throne which Varys said might have been better for someone who didn't want it. But I chalked it up to her seemingly being the last Targaryen - following the death of her evil brother - and thus it being her birthright, and also wanting to be a better ruler than Westeros has long seen. There is a reason Varys chose her in Season 5, he wants the people to have the best possible ruler for them, and he did try to reason with her like she said before ever going behind her back, which he did when he started to see her turn despite that.
She seemed quite put off when Jon revealed he was the true heir to the throne, and once said he was trying to take what was hers, even though it was actually his. But he was willing to go with it coz he didn't want it.
Let's take note of the fact that, if she absolutely had to ignore the bells and take revenge for Missandei and Rhaegal, she could have just destroyed the Red Keep, all those civilians weren't even in the way, and without the Scorpions, the soldiers on the ground couldn't do anything to Drogon. Also, Arya would've assassinated Cersei and cut the head off the snake, though not sure where the Hound would've got the fire to kill the Mountain with, but he'd have probably started rampaging and gotten himself killed by Drogon sooner or later. And Euron's fleet was already destroyed.
I'm sure Jorah would've been heartbroken to see what the queen he died for had become.
Making her the villain wasn't a series-ruining calamity for me (like Avengers: Endgame erasing the previous films would have been), just a little disappointing like killing Varys, Margaery, and two of the dragons. I expected a far darker ending so I wasn't overly disappointed. I was sure she'd probably have to die to remove her from the equasion and make Jon king, but I thought that'd be against Cersei or the White Walkers, and Jon didn't even become king in the end.
