I really don't think it is fair for anyone to be "armchair quarterbacking" the officers or the family. None of us were there so we don't know exactly what happened. The scene could have played out in many ways, but police officers don't always have the luxury of taking longer than a few seconds to make a decision. The family may or may not have feared for their lives. Nobody knows the events that led up to the incident so we can not judge the family for nat taking a different course of action either...
Maybe the man could have been subdued without the use of lethal force, but is it really a police officer's job to fight an armed man while being unarmed?
What if the police left the man in his home and he killed himself and/or a family member(s)? You better beleive that the police would be under fire for that.
if the police had cleared the house of parents and maybe got a preacher or hostage negotiator, and even those bean bag guns I saw cops on that tv show using they might not have had to shoot the guy. if he committed suicide while they were gearing up it would have caused a lot less commotion than when they have to shoot someone
I would guess they would be getting fewer calls now from families that have someone acting wierd in their house.