Here is my estimate on Harry's current level of raw strength. This is what Mab say about the Winter Knight power in Dead Beat.
"Things have changed, wizard," Mab said. "You know the kind of power you face in Kemmler's heirs. As the Winter Knight, you would have strength far outweighing even your own considerable gifts. You would have the wherewithal to face your foes, rather than slinking through the night gathering up whispers to use against them."
We know that one of Kemler's heir is Cowl, who is as strong as a senior council member. I think Mab statement can possibly mean one of two things:
1. Winter Knight's power alone is as strong as any of Kemler's heir which means it is as strong as any of the senior council.
WK power = SC power
or
2. Winter Knight's power is enough to make someone like Harry to become as strong as any of Kemler's heir or as strong as any of the senior council.
WK power + Harry's talent = SC power
In Dead beat, Harry had Hellfire which may or may not be accounted for in Mab's statement. And Hellfire is suppose to be equal to soulfire in power.
If it is accounted for then:
WK power + Harry's talent + Soulfire/Hellfire = SC power, which is Harry's current power level by the end of ghost story.
But if the first interpretation of Mab's statement above is true, than Harry's current power level is:
SC power level/ WK power + Harry's talent + Soulfire. And that is off Demonreach. A bit high for my comfort.