Gotta admit that I like your scenario.....but I just think Hank is too much of a stand-up guy to go bad...especially after he was shot and paralyzed
I think the show has two main lessons.
1) Everyone breaks bad
2) Everyone has some good in them
We saw Mike, a stone evil dude, and fell in love with him as he played with granddaughter. We saw Walt and felt sorry for him crying with cancer, and now we see him poisoning kids to get his enemies firebombed with wheelchairs lol.
Wifey broke bad, laundering money. Hank took the $ for rehab, knowing it was illegal gambling gains.
But I think in the end, Hank ends up breaking badder than everyone, when the czechs or cartels try taking out his wifey. hank has the TRAINING to be the gunner. He has the top job at DEA. He doesn't want to sell drugs, but he does want to protect his family. He'll step in shit investigating walt. Walt will go on the run. Hank will end up breaking the law bigtime, arriving at crime scenes he caused, etc.