There is no “proper form,” that’s why the New Testament and the apostles are so vague on the subject. The church adapts itself to differing cultures, adaptability is one of the great things about christianity.
If it was such a critical question to have a single form, it would have been addressed. The early church saw two influences in this issue. One was the more “elder” oriented Jewish tradition of the Beth Knesset, the other the hierarchical traditions and lesser educated state of the gentile world.
As the church moved into the gentile world an episcopal form was probably an excellent choice. At that point, the church was drawing millions of illiterate believers (which also explains the rise of icons as educational tools which morphed later into worship materials, which in turn evolved into objects which unfortunately became widely misunderstood as having inherent powers).
But we don’t live in that world, the pattern of a single or a small handful of educated specialists implies that the general populations do not have the Holy Spirit informing them, that they have no easy access to the scriptures or scholarship and that their understanding is irrelevant. Now that the laity is often well informed, often can be well inform, the culture of the church is different.
Some people grow in faith through the Orthodox or Catholic or Anglican forms, others thrive in Presbyterian environments, and still others in Congregational forms.
Being one in Christ does not mean being one in style. Variety can be our friend.
In point of fact, the Hellenistic people of the Levant, and of course of Greece, were highly literate.