Since they put the viewer in the point of view of Walter White it didn't occur to me how awful of a person Walter had become until the moment he died.
I still wouldn't call him a bad guy, I mean that's debatable. I think his intentions from the start were good but he was slowly but surely corrupted by the drug business because he could play by his rules, and not anyone else's.
That's just how I perceive his character though.
I also love how his new identity puts him in the state of New Hampshire, where I live
But yeah, amazing show, all the characters felt like legitimate people.