The fact that you mention hating Walt is interesting. I don't hate him, and I don't think my flatmate does, either. I think I knew from the start, as most people did, that he was going to get to this point, going to get this bad, and that has had an influence on me and how I interpret his character: the horrible things he does doesn't leave me thinking "wow, how horrible", but rather "holy shit, that was fantastic, look at how terrible he's getting". There was a while during which I really hated his character, but it wasn't because of horrible things he had done, but more smaller things, like the way he acted and treated other people - really minor stuff compared to murder et cetera. I'd be interested to see how other people feel about his character. Thoughts, b_b, onehunna? (I'll refrain from tagging TNG and MK in case they haven't seen it yet).
I hate Walter. He's pretty much gone full antagonist for me at this point. Dude is a despicable human being--how could anyone even argue otherwise? He's consistently shown that he will commit any atrocity to save his own ass. He lets his own pride and ego get in the way constantly. I think the major turning point from 'relatable character in a desperate situation' to 'total villain' was when he made the choice to poison Brock with the Lilly of the Valley. After that he went from Walt the dying high school chemistry teacher turned meth cook into Heisenberg, straight up. To me, Jesse is 'the protagonist' of the show--he's the one I'm rooting for. Walt can eat a dick.
See, I'm not sure how or why but I think I've developed a disconnect of sort from Walt and his actions. I think it probably stems from the fact that I first started watching Breaking Bad as a study in a media studies class, so spent ages analysing the show and his character - something that I still do (it's probably actually my favourite part of the show). The one thing that stuck in my mind was an interview with Vince in which he said something about the entire series essentially being an experiment of sorts into how long it would take him to transform Mr Chips into Tony Montana. I think because of this I've always approached the terrible things he's done in this nearly comic way. I think if I didn't have this view, I'd probably hate Walt much more. As it is, I just love seeing how terrible he can get. Jesse is my favourite, though, definitely the protagonist in many ways. He's done some pretty bad stuff, too, but he has a conscience, he's the one who has grown the most throughout the show (whereas Walt has less grown and more self-corrupted).
I completely agree that the Brock poisoning was Heisenberg's real coming out party. After that it was obvious that Walt no longer cared about anything beside being the king, not people, not friends, not even money anymore. Money, his original motivator, is now completely inconsequential to his goal, which I think is to shit on the world that sleighted him. Although the look on Walt's face when he shot Mike still was one of horror.