To know how much more powerful *Harry* gets we might need to consider how his *allies* get more powerful/knowledgeable as well...
Except Murphy. She's been offered power, yes, but she declines it. She can take up a Sword any time she wants, but she won't. Harry has to push and prod her to take it up any time he needs her to.
Murphy Started out in Storm Front in charge of Special Investigations. So, not as important as Homicide or Vice or anything, but it was her own department and she was in charge. Then she lost that and became a mere grunt, and now she has lost that too.
Gard even offered her a shot at working for Monoc, where she might have gained special supernatural training, access to large resources, and who knows what else. (Yes, that last sentence was pure speculation on my part)
Power and influence in the mortal world? Lost. Supernatural power. Declined, repeatedly. Murphy is on a downward slope. In a series that has Free Will vs. Power as one of its themes, Murphy has chosen Free Will.
EDIT: I just read what I wrote. Holy crap, the only time she does take power (the sword) is when Harry influences her. He really does influence people to become stronger.
Even when it costs them a little Free Will and an angel turns them into a sock puppet.