@Ishar the energy to investiture conversion is also of intrest to me, I would like to work with you on it if you're willing.
Nightblood is releasing corrupted breath, so I think that the smoke should be compared to the god-kings aura, in which case that is a huge amount of investiture.
To the best of my Understanding the Atium was connected to what was essentially a splinter of Ruin that he did not contain, he could have retreaved the Atium and it's equal power but when burned it returned to the splinter, not him.
Anti-lights are rather new, I expect we'll soon know more.
Perfect gems could be leaking, just at such a slow rate that Rosharans are unable to measure it.