Here's a great, lengthy interview with Pike via Electric Literature. It's from 2019 and covers a lot of ground. If you've been listening to the PikeCast, you'll know they have questions for Pike, and many of them are somewhat answered here. Choice excerpts below:

SS: I remember feeling as if your metaphysical worldview shifted after the first few books. Did you have a spiritual awakening, or simply become established enough that your editors supported you playing with different religious philosophies and mythologies?

CP: Well, I was always curious about metaphysical issues. I was raised Roman Catholic, and I guess I was a strict Catholic until my first year in high school. But I remember I didn’t feel anything with first communion, and I told my parents and they were like, “Well, you’re not supposed to feel anything.”

I had asthma when I was young too, and it was quite severe three months out of the year. I found out only later I was allergic to olive pollen, and in the city I grew up in, Whittier, there were olive trees everywhere. I got pneumonia, and one night it almost killed me. I had a near death experience.

I was outside my body, and I was back at my elementary school. It was amazing. It was euphoric. It was the way people describe near death experiences. And I sensed some being near me, who basically was telling me “this is not your path,” and I didn’t even know what that meant. But I also noticed there was white chalk on the ground, and this was at the back of my elementary school, which I hadn’t been to in a long time, and I don’t know why there was white chalk on the ground. Now this was a part of the elementary school that no one went to even when I went there.

After it was all over, I told my best friend about it, Hans, and he said, well, we should go up to the school. We went there and found all this white chalk on the ground, the kind of white chalk you would use to mark off a football field on the grass, or soccer. And so, it was a very real experience outside my body. So even when I was quite young, I had this fascination. First it was about astral projection. But in reading all those books, I kept stumbling across meditation and yoga. I started meditating in high school. I learned [transcendental meditation].

[...] SS: Why were all (or at least nearly all) your female characters such attractive, white girls?

CP: It was impossible to write YA in the ’80s and ’90s and not notice that the covers all had pretty white girls on them and little else. When Simon & Schuster began to publish my books, they were very open with me. They told me I could write what I wanted as long as I sold tons of books. [laughs] But seriously, I thought it was time I addressed a few of the stereotypes I was seeing in the field. My first book with S&S was Last Act, and I asked if I could make the main character “a normal-looking girl.” I didn’t want her to have to resemble a model. That worked out fine and two books later I did the Final Friends Trilogy, and created two important characters that were not Caucasian. It may seem silly nowadays but I felt kind of proud of myself to have a Black guy and a Latina young woman on the cover of my books.

But then — I ceased pushing for a variety of races to play my characters. Was it laziness? I don’t know, maybe. In fact, I don’t think it was until Fall Into Darkness was published in conjunction with Tatyana Ali starring in a Movie Of The Week that I had some color on one of my covers. That was not S&S’s fault, it was my fault. I was very popular during that period, I could have insisted on the race of my characters. I could have added some color to the entire YA aisle. But I didn’t, I let the whole thing slide. I wish I hadn’t.

[...] SS: I remember at least one book, Master of Murder, in which the character had a parent with an alcohol problem, and in your other books, absent parents were not uncommon.

CP: You know one reason I didn’t have adults in my books too often was because of something Jean Feiwel told me when she was editing Slumber Party. It was my first book and I took what she said to heart, because she was considered the best YA editor in the business. But Jean said she did not think adults worked in YA fiction very well. That it was better if the teenagers had control over their environment. It gave them a sense of empowerment and kids like to read that. (Source)

Loads more at the link.