I asked why she didnt like screwtape letters and she said it was ungodly, like having a dialogue with the devil. It did remind me of that new age book 'conversations with God' by neale donaldson walsh. Im not sure if that was meant to be fiction or true but it was touted as non fiction. But you do have to beware of channelled writings like that.
What most people arent aware of is that anyone whos dabbled in the occult and actually many fiction writers do this, will get demons talking to them.
Again, I fail to find evidence of the occult in C.S. Lewis' books. And what is your idea of "dabbling in the occult"? Does that include just studying mythology, which Lewis did? That's pretty strict.
Some people dislike the Screwtape Letters, which I understand, but for many Christians it was insightful. Lewis uses strong irony throughout the entire book; I do understand people being uncomfortable, though, with reading from the demons point of view. I felt, however, that it wasn't glorifying the devil, but cleverly giving Christians advice on how to spot temptation and avoid it.
No one is trying to claim that C.S Lewis' writings are above the Bible. Many people enjoy reading them because they contain valuable insight. Lewis' work actually helped bring a lot of atheists to Christ; an atheist will not read the Bible and immediately think "Wow, this is all so true and makes perfect sense to me!" Sure, a few have before; but most are going to analyze and be confused by it because they won't fully understand it. That's why it's important for Christians to have evidence and logical reasoning to back their claims, which Lewis displays.
Mere Christianity isn't necessarily geared towards Christians who already solidly believe in the truth of Jesus Christ. It is for the unconvinced and for new Christians, which is likely why you personally found it boring or uninformative as you are not new to the faith.
NO book can compare to the Bible. That is obvious; everyone knows this. But it can be difficult to understand and make sense out of sometimes. Look at the laws in Leviticus; if someone who had never read the Bible picked one up and started reading Leviticus, do you think it would make much sense to them? That's why it's important to have good Christian literature as well., such as Mere Christianity.
And as far as Narnia goes, it is a work of fiction, well-done in my opinion. There are important Christian themes that can be found in it, especially for children. I think it's unfair of you to doubt Lewis' Christianity just because you don't like seeing witches in his book (and I'll remind you that it presents witches the same way as the Bible: negatively). And there is no such thing as someone being a better Christian than another, as we are all equal in God's eyes.