I agree that you can seek knowledge about the outer gates so long as it doesn't come from beyond the outer gates. So using a library that has information about how to fight outsiders is fine, so long as the book isn't from outside.

As for the lawbreaking feats leaving a mark that can be detected by the sight and soulgaze, my understanding is that such things are indicators but may not be completely reliable. Otherwise the wardens would have a much easier job. The Korean warlock that they mentioned confirming guilt by soulgaze in PG was so far over the bend that it was probably fairly easy to see, especially for someone of the Merlin's skill. It is also my understanding that such things are easier to detect the more recently they have been used. In Backup,

Think of how vaderung wears two mantles. You could be the emissary of two powers, perhaps even conflicting powers, but maybe not both at once. They could be legally and perhaps metaphysically distinct entities that your character has to juggle. That sounds fun.

I think that one of the important things to keep in mind is that you have to be in the same "space" as someone to affect them. To initiate physical combat you have to be in the same physical space. To initiate social combat, you need to be in the same social space. In order for a conflict to be both physical and social the characters would need to be in both the same physical and social space. So you might be in a physical conflict with a gang leader and use a social attack to undermine his authority over the gang. But just because you are in the same physical space as someone doesn't mean you have the ability to affect them socially.

My view is that there may be a difference between what the universe thinks and what the council thinks. As near as I can tell the universe is not a moral creature in the dresdenverse and the laws of magic have little to nothing to do with "sin". Consider that killing somebody with a gun is fine, but killing somebody with a fireball is not. My understanding from what Harry has said in a few books is that magic is generated by life and using magic to directly destroy life sets up a negative feedback loop that permanently removes some magic from the universe. Presumedly the taint of dark magic is what wells up to fill the void. If you use magic to light a house on fire and that fire then rages out of control and kills some people after you stop pumping magic into it, no lawbreaker stunt. Similarly, if you forzare someone off a building you also get no lawbreaker stunt. What matters is the force of life causing death. However, the council's views on the first law may be more complex. To them the laws of magic don't just represent the physics of how the universe works, they represent a social order that must be maintained. A warlock might be clever enough to avoid direct lawbreaking (for instance, enchanting beer with the force to bring on unnatural lust in any who drank it), but the wardens would hardly care and no one would criticize. Example: Harry's love potion in storm front did not violate the fourth law as far as the universe was concerned (he didn't get another lawbreaker stunt for it), but directly entering someone's brain and tweaking them to love you would certainly violate it because twisting their brain when you were directly connected would also twist your own. The potion acts as a buffer that prevents you from becoming twisted by the act. If the wardens found out you were spreading love potions around, however, you probably wouldn't get a chance to plead your technicality at trial.