Also Lily's spell is far hotter than almost anything we've seen dresden do in the books. I think some of his Hellfire empowered stuff might come close, but it had the same instantaneous obliteration effect on Fix's sword
Larger, yes, but not hotter. Harry says his lake-freezing fire-column spell in WN is "hot enough to vaporize ten-gauge steel" (and there was no Hellfire in that spell, just energy gathered from the environment via regular wizard magic). Harry doesn't throw around fire magic on that scale very often at all, but it is within his capabilities.
I think he also describes a fire spell in Changes as being as hot as the sun or something, but there was Soulfire in that.
That spell is more powerful than anything we see Harry do before he's Winter Knight (afterwards, I think the warehouse-lifting-iceberg in CD is comparable or stronger) but it's not on a whole other level.
I was just about to say that. Molly has her wizard power in addition to her Lady power.
I don't think her wizard power is all that meaningful on this scale in "raw power" terms.
However, Molly's core talents of illusion and subtle magic work really, really well with the way the Sidhe tend to do things. Give her enough time to really learn how to adapt her existing skills/talents to her new power, and she'll be incredibly, terrifyingly capable. But that will be because of her skill/talent rather than just raw power.
(Luccio says in SmF that even before her body swap, she had less raw power than Harry. But she was far more capable.)
Yeah, but Jim (who knows better than Uriel) has said that it's possible to lose your soul even without turning into something other than human, if you're terrible enough. So it probably does get whittled down bit by bit.
If we're talking about the same WoJ (the one that talks about "growing mold on your conscience"), I think that means "lose your soul" in the sense of damnation/turning evil, not turning into a being with a radically different kind of spirit.
To be fair now i've napped a little it's also not clear whether or not JB ran the math on the trick he had molly pull at the start of Cold Case.
I'd think not, since Molly compares the energy required to "military grade munitions"; I don't think she means nuclear weapons from the way it's phrased.
The math for me come sup in the 400Kt+ range,
Well, it's described as ten feet deep, half a mile around (has to be more or less a half circle since the boat is only twenty yards from shore). So that's about pi * (800 meters * 800 meters) / 2 (for a half circle) = very close to 1 million square meters of area.
It's 10 feet/3 meters deep so that's about 3 million cubic meters of ice.
The density of ice is about 900 kg per cubic meter, so that's about 2.7 billion kg (2.7 million metric tons or about 3 million US tons) of water frozen.
The water in the Alaskan seas is likely fairly close to freezing already, but the absolute minimum energy removed to freeze water (if it's already at freezing point) is the heat of fusion, 333 Joules/gram. 2.7 billion kg is 2.7 trillion grams, so 899 trillion joules (899 terajoules). That's the equivalent of roughly 215 kilotons of TNT (1 ton of TNT = 4.184 gigajoules).
That's fairly close to your 400 KT given how rough this is.
On the other hand, we don't know how drawing on Winter Ice works energy-wise. If it just involves freezing stuff by dumping the heat into the Nevernever, the effect might be more like opening a bunch of micro-portals to the NN (which can't really be calculated in physics terms) rather than actually handling all that energy directly the way Harry does with regular wizard magic.