Fake Ghost Pirate said:
As a believer, lovecraft fan, and (amateur? student? In-Training?)Anthropologist, Church Historian and Theologian, I have a couple thoughts...
First off, August Detleth is more-or-less responsible for introducing greater Christian themes and Symbolism into the Lovecraft mythos, though Lovecraft himself had more, well, almost nihlistic approach to life. His readings are actually somewhat fascinating to me for that reason, he wrote about what scared him, and what seemed to scare him the most was the insignificance and limited scope of mankinds existence (Which as a Christian, actually brings comfort to me) - but that is getting into another topic entirely and I'll spare you all some interesting lectures.
I probably could go on, but ah, the heck with it.
As for the Deadly Sins and Ancient Ones...
We have Wrath, Sloth, Envy, Greed, Lust, Pride and Gluttony.
Sloth is the easiest - Tsathoggua's power is Malaise, which is practically another word for Sloth. Dude won't even move.
Gluttony is Cthulhu, since his whole goal is to OM NOM NOM all mankind (Campus Crusade for Cthulhu says: Cthulhu Saves... Some for Later!)
Wrath is likely Yig - he is after all, rage.
I think I have to go with Shub-Niggurath being Lust, as her cult is based on fertility cults and she has penchant for making terrible tree-goat babies that are scary as all get-out.
That leave Greed, Pride and Envy, and for Ancient One's those are more difficult.
If Azathoth is the most powerful ancient one, he is likely Pride. As Pride comes before the fall (or utter destruction of all things) the Blind Idiot God at the Center of the Universe fits nicely there.
I think I would go with Yog-Sothoth for Greed, not due to him himself, but to his Lurker herald, who allows poor fools to gain short-term power in exchange for selling their souls.
Envy is Nyarlathotep, for he takes the forms and masks of others and makes them his - not to mention his unfairly cruel herald holds tightly onto his possessions!
And Hastur is Madness.