Mmm yes I think it is definitely more than merely just taking away TWG's toys. I suspect there is real power involved, and that the war is more of a cold war between Heaven and Hell. Souls as a power source has been done before, and I am sure Jim will have an interesting take on how it works.
Snark Knight: Not sure that the Multiple Man act was all the different versions of Before coming together (unless of misunderstand your comment). I think it far more likely he is simply strong enough that he can be a sort of gestalt consciousness, inhabiting many vessels (which he perhaps creates himself). Only mortals would be so limited to operating the one meatsuit, I think stronger beings could have many avatars being used simultaneously. Which is not to say mortals don't have that potential, but our earthly physical limits would likely prevent this. Lea gives some hint to this when saying that the brain is not the only storage facility for memories, in fact often a poor receptacle for such things. The body seems to be an actual limit to the full potential of a Soul. Not sure what you mean about the "there-but-not-there" behaviour...were you referring to his power being impossibly deeper than Mab's (the photo of a sculpture vs the actual sculpture itself)? If so, I totally agree. But I think it is because the Outsiders only ever put a portion of themselves into Reality, they have more "essence" than is truly comprehendable and compatible with Reality and so are limited by whatever amount of themselves has been "invited" in. Think the Void Lords in WoW or the Daemons of Chaos in Warhammer/40K, or the Outer Gods in Lovecraftian Mythos.