I mentioned previously that I think PC (I'm abbreviating all titles to their initials from now on) is a better book than LWW, because it's not on auto-pilot. I think I'd also rate SC considerably better than VDT. The problem with VDT is that it's more a collection of disconnected short stories than an actual novel. They go from island to island, and each island has got something interesting going on, but they don't really have anything to do with one another. If it were an RPG, it would be one of those adventures that consists of nothing but random encounters. So I liked SC a lot better, because it has an actual plot.
I'm starting to think the religious angle of the books is being seriously overplayed. Someone on my friends list said, and I have to agree, that while there are elements of religious allegory in the stories (Aslan is obviously a Christ figure, for example), the thing is that you'd never notice them if you weren't already familiar with Christian lore, because they're all mixed in with other things. (Which makes it not very surprising that I -- and many others -- totally missed them when we read the books as children.)
Let me give an example of what I mean. Okay, so in VDT, Eustace gets turned into a dragon by sleeping on a dragon's hoard and thinking selfish thoughts. He gets transformed back when he encounters Aslan at a well. Eustace wants to bathe, and Aslan tell him he has to undress first, so Eustace scratches off the outer layer of his reptilian hide. But that doesn't do it, so he scratches off another layer, and another, and then Aslan explains that Eustace will have to let him do it. And Aslan pulls off all the skin, revealing that he's a human again underneath, and tosses him in the pool.
Okay, so this is a nice little allegory about Christian theology, illustrating the idea that salvation comes only through Jesus, and not from one's own actions. Lots of related elements, like baptism, and "trading old garments for new", and being washed clean, and so on. Lovely.
But then we have the island of Ramandu, where a "retired" star and his daughter live near Aslan's table. Every evening, the food on the table is magically renewed, and every morning, a great flock of white birds comes flying out of the dawn, descends on the table, and eats or carries away everything that's left. One of the bird brings Ramandu a fireberry from the Valley of the Sun, which he takes away a little of his age, so that eventually he can rise into the sky and become a star again.
Which is related to the Christian idea of... well, nothing, really. I mean, you can make parallels if you're looking for them (maybe the birds represent the Holy Spirit, and tables are an important symbol of fellowship, and, um...), but it's not like the baptism metaphor. There's no simple mapping. And there are a LOT of these things. Most of them are more like Ramandu -- random, mysterious, magical, maybe with a tinge of Christian symbology but not especially religious -- than they are like Eustace's redemption.
Aslan is a helpful supernatural ally who is generally benevolent and infallible, though not always plain-spoken. And the characters react to him as such. But that's not a uniquely religious pattern. The characters in Steven Brust's books react in very similar fashion to Sethra Levode, an ancient sorceress who is helpful, supernatural, generally benevolent and sufficiently experienced (thousands of years old) to be effectively infallible -- but definitely NOT a Christ figure. So while the readers might see the parallels between Aslan and Jesus, as far as the books treat him, he's just a friendly superpower.
Anyway, I guess my point is that having re-read the books from a critical adult perspective, my conclusion on the whole issue of religious content is that there's definitely some of it in there, but it's about as prominent as you decide to make it. No more and no less.
P.S.: I wrote this while really tired, so I hope it's coherent, but I make no promises.