is that decision late in book seven to have literally zero Slytherins side with the good guys. Basically going back to the simplistic take of the first few books, and largely undoing her own effort to make Slytherin a bit more human with characters like Slughorn and of course Snape.

As you pointed out on Facebook, a lot of the people you know are lawyers. Just saying.

She could and she did, before ruining it at the moment supreme.

He's a kid. A single child brought up in a snobistic, elitist, racist family with delusions of grandeur. He doesn't break out of that easily, lacking Sirius' rebellious streak, but as Dumbledore easily sees, his heart isn't in it.

I think you mean because he looked like his admittedly obnoxious father. The complexity of Snape is one of the elements that make the books so much more than the children's books they appear to be. He's mean and cruel to his students, the nasty kind of teacher who likes to be feared and score points with students by humiliating others. And I don't mean Harry, who can take it and whom he is, in a twisted way, trying to prepare and harden for what he knows awaits him. I mean his behaviour to other students. But he's also loyal at heart and remarkably brave, playing the double agent for so long. He's the kind of person you need to win wars - the kind willing to do what it takes to get the job done. You won't get there with only the heroic kind of people.

Also, I don't think Snape ever actually hates Harry, and certainly not at first sight. It's a lot more complicated than that.

Really not that terrible at all. A lot of successful people in business or politics or academia or whatever have more than a little Slughorn in them, which I dare say was the point. He seems like Rowling's way of bringing a little balance back and reminding her readers that there's more to Slytherin than just 'evil genocidal maniacs'. There's a reason why Slytherin was one of the four founding houses, after all - which makes that moment in book seven that I mentioned all the sadder.

Another aspect of the series that's pushing the children's literature barriers, is Rowling's nuanced take on how easily 'good' people can cooperate with or even promote evil, out of fear or ambition or misguided beliefs.

I think Cannoli had a few good points there. I would add that a not negligible part of HP readers has at least some familiarity with fan fic, many of which went for alternative takes such as telling the story from a Slytherin perspective, or at least a non-Gryffindor one. And yes, the epilogue counts as fan fic.