I’m only a lay person, and for a bit of background I was baptized confirmed LCMS, went non denomination evangelical for a number of years, came back to the Lutheran faith as I felt they were more connected to church history and had the sacraments rightly administered at first ELCA and then to confessional Lutheranism(WELS) when the ELCA went too liberal(re:abortion). However, I have been studying both the RCC and the EO as much as I can because I am coming to believe Apostolic succession is important. That is my journey so far in a nutshell. I would love to see the church be one again- its a dream of mine-but it will be difficult. in practice.
Here is what I THINK might happen.
The Lutherans and Historic Reformation churches first, then the East West schism finally.
Actually, what I think COULD happen is some churches that accept the Papacy would go To Rome,
the churches that don’t accept the Papacy go East.
Like a backwards time machine.
Then finally, reunification between East and West.
So, in the near future-LCMS and Anglican and Methodist and Reformed unite with Rome.
Baptists, and Non denominational reunite With Orthodoxy.
Farther on in the future-East and West reunite.
Of course, there are issues to be resolved such besides the Bishop of Rome such as:
Monergism vs Synergism. Reformed, LCMS,ect would have issues with that. Some Baptists and Non denominationals not as much so I can see them reuniting with Orthodoxy more in that case.
Divorce/Remarriage.
Same Sex Marriage
Abortion.
and of course Justification vs Sanctification. But we already have Lutherans and Catholics trying to hammer that out.
So I think Lutherans first, before Constantinople.