No, I didn't have a similar reaction with Dexter, as I believe the character was scripted to behave as he did. The death of his mother set him on a fatal course, and the fault for that would be those that caused her demise. His character was ingrained at an extremely young age, and without someone realizing and addressing it, he was never going to change or improve. I certainly wouldn't consider him a good guy, though!
You cited one of the more egregious actions White took, and a rather nasty one, yet the one that had me howling at the television was what he was going to do to that child. The Jane situation was almost as bad, but for me the child endangerment trumped it by a kilometer. The planning, the callous disregard for the child, and this coming from a former teacher?? Uggh, even now my stomach churns just thinking about it!! And even how he often treated his own family, and Jesse, and many others, beyond despicable. I was totally in deaths' corner all the way where Walter White was concerned. It just wasn't as brutal as it should have been.