In my book, The John also called Mark: Reception and Transformation in Christian Tradition (Tübingen: Mohr Siebeck, 2020), I argued for an early Christian identification of John Mark with the Beloved Disciple/John the Evangelist.
Pierson Parker, who likewise argued for the identification of the Beloved Disciple with John Mark, observed that the hypothesis could have implications for our understanding of the Deutero-Pauline epistles.
These letters are often dated (and doubted) based upon a supposed evolutionary line of theological development from Paul to his later interpreters. Their doctrine of the divinity of Christ is seen as too developed; indeed, many have likened it to the Johannine conception.
But in Colossians Paul mentions John Mark as among his co-workers, and this could, on our hypothesis, account for the Johannine flavour of the preformed traditions in Colossians, which speaks of Jesus as the image of the invisible God through whom God made the worlds.
The Johannine Circle
John Mark is associated with Antioch and Syria in Acts and in later ecclesiastical traditions (e.g. the Acts of Mark).This may complement the work of Oscar Cullman, who posited that the Jerusalem Hellenists carried a proto-Johannine theology to Syria, where it influenced Ignatius, the Odes of Solomon, and Ephrem. Perhaps John Mark, as a representative of this theological tendency, introduced it to the Pauline communities of Asia.