As for "Mad Dany," I would say that Dany was always kinda mad. She walked into a funeral pyre, threatened to burn cities multiple times, fed an innocent man to her dragon, engaged in collective punishment, tortured people, seems to enjoy killing her enemies, forced a man who's father she'd killed into an engagement, and burns people alive. She was always a tyrant, it's just that Dany's story embodies how tyrannical methods can be alluring when leveled against evil systems, and how a change in our perspective shows the brutal side of that tyranny in a much different light.
Dany doesn't change from good to bad, our perspective on her is what changes. Dany was good when she was destroying a system that was totally abhorrent to the viewer, and when the people were on her side. But in Westeros, the people do not choose her, and her efforts to dismantle the abhorrent system of Westeros is seen as more problematic because that system has been humanized in a way the system of Slavers Bay never was. Futhermore, Dany is corrupted by the violence she engages in, and is too consumed by her own desire to see herself at the top of that system. Ultimately the Iron Throne is a story which corrupts Daenerys.