I'm sorry, but I simply do not have a problem with Black Widow killing people. Our perception of comic books, as old-timers -- the Black Widow who swings from ropes across rooftops with Daredevil on adventures...that character doesn't exist anymore.
Times have changed. For better or worse, the Avengers are pretty much affiliated with SHIELD now -- hell, they have been for years now. Black Widow carries pistols. Wolverine's a part of the group. And they sanction people.
Do I wish it was the way it was back in the day, back when Egghead's death prompted a trial? Sure I do. Comics were an easier read then, were more fun.
But that era's been gone for at least a decade now, if not longer. I wish it weren't so, but it is, and I think limiting Hickman's interpretation of Black Widow based on an era that has clearly passed is...well, I think it's just not productive or realistic.
*Sniff, sniff* "Damn it, Diana...If I'd known they would trade us in for a JT Krul-written Captain Atom and "The Savage Hawkman," I'd have let Superboy-Prime destroy all reality.""Superman flies and is really strong...what the fuck else do you need to know?!"
-- Hitler, expressing his displeasure about DC rebooting and complaints about continuity