Regarding the Craster comparison, that has some accuracy.
The problem arises in the difference between the nature of the sacrifices.
While I don't know if there is an exact analogue between the Others and Judeo-Christian demons, the Others clearly represent Martin's interpretation of the Uncanny Valley.
The God of the Old Testament is vengeful and proactive, but he actively wages war on behalf of his subjects against Satan, his diametric opposite. I would say that the Old Testament God could be compared to R'hllor, and the attempted sacrifice of Edric Storm and the burnings of various other individuals by Melisandre are a much closer equivalent to the sacrifice of Jacob.
Craster's offerings resemble the holocausts of the ancient Egyptians, who enslaved the Jews worshipping the Old Testament God.
Thus we have two parties in this allegory, both using human sacrifice to achieve their ends while working against each other.
The Others, comparable to the Egyptians, accept Craster's sacrifices as fuel for their endeavor to reconquer Westeros from the humans.
R'hllor's followers, comparable to the Jews, follow a mighty and unforgiving God who seeks to relieve them from their plight by casting their enemies into an eternal, fiery torment.
Anyway, this is obviously overanalysis, but that's one way of viewing Melisandre's quest from a Biblical perspective.
Edited by MVPacMan23, 22 April 2012 - 02:10 PM.