I would like to address the idea that the primacy of a bishop is only honorary and carries authority. A study of the primacy of the Patriarch of Constantinople was undertaken by Lewis Patsavos in his essay “The Primacy of the See of Constantinople in Theory and Practice”, which is found on the website of the Greek Orthodox Archdiocese of America. He writes in his introduction:
“The position of honor accorded the Bishop of Constantinople brought with it genuine authority (exousia). This is made evident by several factors including: appeals from other churches; the importance of the Resident Synod (Endemousa Synodos); the authority exercised by several renowned patriarchs such as Saint John Chrysostom, who involved themselves with matters beyond the territorial limits of the Church of Constantinople (such as evangelizing the Goths and Scythians among others, and reforming the independent dioceses of Pontos, Asia, and Thrace).”
He then discusses at length historical examples of this primacy. He concludes:
"The history of the Ecumenical Patriarchate of Constantinople demonstrates a longstanding canonically-based tradition of leadership within Orthodoxy. This tradition is seen in the moral authority it exercises, as expressed in the events enumerated above. It brings with it special privileges, one of which is the right to take initiative, with the consent of the other churches, in general ecclesiastical matters effecting them all. The presveia times fully recognizes that all bishops are equal by divine institution, having received the same degree of episcopal grace and sharing the same unbroken apostolic succession. This does not mean, however, that all bishops are equal in honor in the canonical system of ecclesiastical administration. They have different titles and different prerogatives, depending upon the status historical precedent has established for them. Some bishops have thereby obtained hierarchical seniority, exercising greater influence because of it. In practice, the tradition of the Church has preserved a “hierarchy of honor” which corresponds to the τιρεσβεΤα τιμής.
The Orthodox Church has always recognized that each area has its own first bishop, variously called archbishop, metropolitan, or patriarch, depending upon the extent of his authority. Furthermore, she has always acknowledged one among them in the universal Church as first. Since the separation of the Eastern and Western churches, the Patriarch of Constantinople has been recognized as first, his authority having been recognized as equal to that of the Bishop of Rome since the Fourth Ecumenical Council.
Before concluding, it is important to state how the hierarchical seniority, status of precedence, and authority of the Patriarch of Constantinople within Orthodoxy are not understood. In the words of Metropolitan Máximos of Sardis: ‘The patriarch of Constantinople rejects any ‘plenitudo potestatis ecclesiae’ and holds his supreme ecclesiastical power not as ‘episcopus ecclesiae universalis,’ but as Ecumenical Patriarch, the senior and most important bishop in the East. He does not wield unrestricted administrative power. He is not an infallible judge of matters of faith. Always the presupposition of his power is that in using it he will hold to two principles: conciliarity and collegiality in the responsibilities of the Church and non intervention in the internal affairs of the other churches. . . .’
Keeping in mind these fundamental concepts of non-interference, conciliarity, and collegiality, it is important to note that as the principal spokesman for all the heads of the Orthodox churches, the Ecumenical Patriarch not only holds πρεσβεία τιμής, but also prerogatives of true ecclesiastical authority. These prerogatives are manifested in his role as supreme administrator and judge within his own jurisdictional territory, and as facilitator/convener for the entire Orthodox Church in general ecclesiastical matters, in consultation with the other heads of the Orthodox Churches. As history has shown repeatedly, his intervention has been sought in resolving disputes and arbitrating sensitive issues in the life of other Orthodox churches. Such, in fact, has been his authority, that without his approval an ecclesiastical act affecting all of Orthodoxy would be considered, at the very least, canonically insufficient.
The authority exercised by the Ecumenical Patriarchate is borne out by history and the canons. It is, however, an authority understood as service according to the example of Christ. It is this image of service which predominates in its relations as πρωτόθρονος with the other Orthodox Churches for the purpose of fostering unity among them and assisting in their mission to the world."
goarch.org/ourfaith/primacy-constantinople
In light of this, I fail to see why a similar role for the Bishop of Rome in a reunited Church would be so unacceptable for us Orthodox.