Brant, JoAnn. John. Paideia Commentaries on the New Testament. Grand Rapids: Baker Academic, 2011.
Clark-Soles, Jaime. Reading John for Dear Life: A Spiritual Walk with the Fourth Gospel. Louisville: Westminster John Knox, 2016.
Hunt, Steven A., D. Francois Tolmie, and Ruben Zimmermann, eds. Character Studies in the Fourth Gospel: Narrative Approaches to Seventy Figures in John. Grand Rapids: Eerdmans, 2016.
This resource covers every character in John (except the Trinity), named and unnamed—including, for instance, “the world.” The volume has several contributors (I wrote on Mary Magdalene). This is a great resource for preaching and teaching. It is now available in paperback, which makes it more affordable.
Koester, Craig. The Word of Life: A Theology of John’s Gospel. Grand Rapids: Eerdmans, 2008.
Schneiders, Sandra. Written that You May Believe: Encountering Jesus in the Fourth Gospel. Revised and Expanded Edition. New York: Crossroad Publishing, 2011.