Hate to tell you but as a reader who has given this a great deal of thought, I would like the character better a different way. Hence my position that I disagree with JB's choices for Murph and Butters starting from the point I feel JB could have written differently. There are people who think the Mona Lisa should have been painted differently too, the counter point isn't "that's the way he painted her". JB has plans for Murph but probably needs her to be able to withstand more combat damage. My guess is that I will still disagree with his choices there too.
She got fenced in somewhat from the beginning, athletically gifted in hand to hand combat, crack shot, smart, cop's mentality about justice and the law. That worked great until she left the police force, she still was able to use her skills, but Knight of the Cross didn't exactly fit her, nor head of a vigilante group. Jim I think had already said, no power ups for Murphy, and her fans seem to agree with that. Keep Murphy as she is, a sane vanilla anchor for Harry, and she is a good fighter as well.
Okay, but time marches on, from the start she if five years older than Harry, and while as a wizard, he is still considered quite young, she is in the middle of middle age, the slam bang fights that she was always so go at, seem less and less plausible.. So in Skin Game it all caught up with her, big time. So now lets consummate the dance her and Harry have been doing for years.. So what is left? Having her killed by a cheap shot after her doing an heroic deed.