When I think of a door getting kicked in, two images come to mind immediately:
Drug raid
Rescuing a hostage
Amateur opinion and speculation only
RSBM.
Chiming in here as a person who's worked in the psychology field, and going back to the first part of your post, a violent sudden, non-retreatable action when the outcome is not known ( the intruding person who kicked the door in could get shot, stabbed, there could be an off duty LE officer sitting there, a mean attack dog rescued from the shelter 2 days before, and so forth)-
the impulsive actions of kicking a door and shooting two adults in their own home speaks to unmitigated and uncontrolled rage to me.
It is an act of stunning violence to invade someone's home by force with intent to kill.
I believe the first reports said the EMS personnel and other first responders to the scene would need crisis counseling.
If that was an accurate statement, it is usually an indication that are violent aspects seldom seen at a crime scene.
It remains my belief that because Jayme is not listed as " possibly injured" in the Missing reports, but her parents were murdered, then she was the target, or she'd have been gravely injured and left for dead or killed as well.
The murders in CT of Dr. William Petit's first family- his very young teen daughter who wasn't dating yet, his older teen daughter and his wife after he was immobilized by recently paroled men who were on drugs and also were totally amoral individuals who fed off each other's bravado
may give some insight into what personality type committed the murders and abducted Jayme.
I hope FBI profilers will look at the psychodynamics of cases where parents were not the targets but their child or children were. These cases are very rare because parents DO die trying to protect their children, and because children are both simple, in that they do not possess money or good survival instincts when on the run, and because a child hostage does become a liability much more visibly and with greater public awareness and reaction when there's a national FBI search in place.
I noticed in the Wausau Herald that the family dog was also not harmed but left in the residence.
While I tend to think this is a part of the criminology, it's also reassuring just a bit to me that they didn't kill the dog sadistically in front of the little girl. I tend to think there was more than one intruder, and possibly an accomplice held Jayme out of sight of her parents' shootings and hopefully, she did not see their bodies at all.
If she is to be found alive, she has to have internal strength and hope in the face of likely great danger.
Stay strong, Jayme. So many people are praying for you and hoping for you, I hope you can feel the love in the midst of all this.