I don't know all the references that AW Admin listed, but I do know that Milton, St. Augustine, and Bunyan were very Christian, as was Lewis. And there's a world of difference between their wildly disparate works and The Golden Compass series, a difference that's at the very core of the story.
OP, and AW at large in this instance, St. Mary Magdalene is a saint who has been revered by Eastern Orthodox and Catholic Christians for centuries. People, including me, pray to her. (Not worship--I don't want to go down that rabbit hole, but we do speak to and petition her.) So, as a character, she--and her circumstances--have the weight of both history and faith.
This is a specious argument. If you are an Orthodox Jew the entire New Testament is, at best, problematical. If you are a Roman Catholic, your Bible is strikingly different from the Bibles of a Protestant, a Russian Orthodox, and a Greek Orthodox; this is because they each canonized different manuscript traditions.
Pilgrim's Progress, while a Protestant literary classic, is heretical if you're Catholic. So is Milton's Paradise Lost; both contain fairly substantial heresies. St Augustine (there are two, by the way) invented a fair amount of what he wrote out of whole cloth; it was extra Biblical.
Protestantism, just for the emphasis on faith alone instead of works, is technically heresy, to a Catholic.
Much of what people think is doctrine about St. Mary Magdalene is in fact, extra Biblical. Some of it was invented out of whole cloth, some of it was conflating later non-Canon gospels with the Canon. And there's confusion as later commentaries conflated various Marys in the Bible (Mary was even in the 500 years before the birth of Christ one of the most common names for women). And then there's the excluded Gospel of Mary, to further confuse the issue. Moreover, the depiction of the Magdalene in psot Gregory and now, is very very different from her depiction today. Hugely so.
The Seven Deadly sins, as noted upthread, are not Biblical at all; they're exegetical commentary. And there are multiple versions of them, depending on which list you use. (The order also varies.).
And yes, of course, any religion should be treated with respect, just like any culture. That's actually the key; be respectful, but that also means having an awareness of the source material you are using.
Which is the reason the OP started this thread.