My philosophical and theological journey from Christian Fundamentalism towards a profoundly different understanding of what Jesus taught was largely the product of independent reading and study. Then later, meditation and more direct perception. Over the course of exploring the subjects covered in Essays along the way, I read a ton.
Below is a link to a spreadsheet that includes notes from hundreds of books and research papers. I read far less now, but continue update this document. Hopefully this material can help expedite or inform the self-directed path of others:
Book Library Spreadsheet: https://tinyurl.com/y3fxry78