The only issue I have with your otherwise excellent analysis is that it tries to negate Dany's benevolence as being false or temporary, as if it were just a mask or something the real, malevolent Dany was just pretending to wear. That I don't think is true. When she does what she does in the books, her emotions are real and legitimate. She honestly does feel for the random peasants being killed and raped. She takes genuine offense at the idea of children being used for intimidation purposes. She does want freedom and better life for common people. What causes conflict in this is that implementing these benevolent intentions is not simple, easy, and can often backfire either due to honest mistakes or malicious scheming from enemies. Something as simple as trying to outlaw slave fighting, a brutal and exploitative industry, gets backdraft from not just people who directly benefit, but people who have this belief engrained in them that it's their right to beat someone (or be beaten) to death for fun and entertainment. One of the defining aspects of the series is that benevolent intentions and even actions that are actually beneficent do not translate to good things happening for you, so even when Dany does act the part of the Good Queen, bad things can still result from it.
The other point is her entitlement and imperialistic tendencies...I agree these are part of her character, but I feel simply saying that leaves an incomplete picture of her. Like, who in Westeros is a democrat? Who even in Essos believes in equality based social and governmental systems? Basically, wildlings and no one else. Characters all over are more or less unquestioning of the monarchical system. The closest example I can think of is when they elect the new leader of the Night's Watch, but that's only an election that takes place in their organization, they don't question why they need to have a king. So, yes, Dany is an imperialist. She believes the Iron Throne was stolen from her by treachery and that she is entitled to it back and if she had to burn the enemy to the ground, she sees it as the right thing to do. And, by the by, it's also not entirely fair to say that she just wants it out of personal greed or power hunger, with her backstory. Growing up, Viserys is the one who was obsessed with getting the throne back, with revenge, and he defined her life by it. And the idea of living in peace was something she entertained, once Viserys died. Then Robert sent an assassin after her, at which point she believed that her life will never stop being defined by her usurpers, so she sets out to get her throne back. The only time her life starts going her way is once she has power, because without it, she's just waiting to be raped by the next Khal that comes out on top.
None of this is to diminish that, yes, Dany is an imperialist and, yes, Dany does want power. But she wants power not just because power feels good in itself, but power is security. Power, she thinks, will be no longer having to fear the assassin's of the king. Power is getting back at the bastards who ruined her life by taking the throne in the first place.
And on that note, yes, Dany is also wrathful. When she thinks your a bad person, then you deserve to die and she relishes in being able to deliver that justice. The witch at the end of book 1 wasn't just some random lady that she picked out of the crowd. It was the woman who directly killed her husband and threw her life into disarray after it finally stablized into something happy (Which, btw, this witch only did because Khal Drogo destroyed her life and the slaughtered the lives of her people. Her last conversation with Dany was telling her how what she did was justice and she was happy to do it). She delighted in burning the faces off slave masters, but she did so because they were slaves. Maybe you believe that no one should take pleasure in the suffering of others and that's fine, but it's simply human nature take enjoyment of the suffering of those you deem evil. It's a very common occurance and one we see contemporarily all the time.
My point here isn't that Dany was actually really good and all her questionable actions are actually all morally justifiable. My point here is that she is was written in a complex way. GRRM didn't write a sociopath that hid her cruelty and sadism in some warped psychological trap, he wrote a complex character who is kind and cruel and well intentioned and spiteful and generous and entitled in various different ways, at different points in her life, for different reasons, which is what made her a great character. She couldn't be defined by any one thing nor could you not understand her actions, in all their varying extremes.
I'm not saying that there isn't a way in which you can write Dany deciding to make that decision in King's Landing, but it's on the job of the writers to not lose the complexity of the character in doing so. I believe if GRRM decides to keep the burning of King's Landing as a plot point, he will do this. That's what is wrong with all this, she just became abjectly evil for no reason whatsoever, simplifying her character to cartoonish evil proportions. And while I do think the points you bring up about her entitlement and wrathfulness and self-image of a liberator are very germaine to the analysis of her character, I think you're using them the wrong way if you're using them to recharacterize her as "No, look, she was evil all along!"
No, she was a complex character that you couldn't fit into a single good or evil, because she was both well intentioned and blind to her flaws, both knowingly wrathful and naively empathetic, both kind and cruel. That's whats so wonderful about the story GRRM tells, it's full of these super interesting and unique people that you can believe exist. Writing Dany the way they did destroys all that because they didn't write her as a complex person with warring desires and motivations, but as a homocidal psychopath waiting to be unleashed.