Finished watching this a couple days ago. What can I say other than "WOW".
The whole show to me was about justifying evildoing. This starts happening right from the start when Walt physically attacks the bullies when Jr is buying his new jeans. Even though most people wouldn't rise to them, yet it's amazing how far we sympathise even when it starts turning into murder.
The show is brilliant in that the point of de-sympathising with the protagonist (Walter) is dynamic. When he watches Jane die, when he poisons the kid, when he shoots Mike? etc. So much of it is justified which makes you question your own morality, which is amazing.
One thing is at the end when he's seeing Skyler for the last time. He begins to say "Everything i've done, I did it for...." skyler interrupts saying "don't say it was for the family", and then he continues "It was for me".
Was he going to say "For me" or "for the family"? In my opinion he was going to say "For the family" but only changed it because Skyler interrupted, otherwise Vince wouldn't have written it in such a way as to create doubt. The line would have continued without interruption. This further backs up how twisted and manipulative Walt had become.
Also, if you watch the Pilot straight after the Finale, Walt's personality makes so much sense. For example how one of the students he beats up in the Junior's new jeans scene says "Psycho" before walking away. We're all initially rooting for Walt, even though two evils don't make a right.