There are three scenarios that could lead to the restoration of an Orthodox Patriarchate of Rome:
1. The Mass Conversion
A conversion on the part of a Roman Pope and the majority of his curia and his cardinals to Orthodoxy, that would cause the Orthodox Patriarchates to recognize him as primus inter pares and respect the Western character of the Roman Church in the West, if certain conditions are met (the integration of Eastern Catholics with Orthodox jurisdictions).
2. The Restoration of a Roman Patriarchate
A Pan-Orthodox Synod condemns Roman Catholicism as heretical and agrees to restore the ancient Roman Patriarchate in Orthodoxy. The Pope elected would lead the Orthodox community in Italy and will attract Orthodox communities from the West. The new Orthodox Pope would become the rival of the Roman Catholic one and might receive Traditional Latin Catholics into his Patriarchate.
3. The Restoration of Communion
After years of religious dialogue, major agreement is reached on most issues. The Orthodox Church would recognize the primacy of the pope while he would rennounce his infalibilty. Eastern Catholic Churches would rejoin their Orthodox counterparts while full communion would exist between Catholics and Orthodox.
Which of the three different scenarios appear more posible according to the different opinions?
I know that when the Alexandrian and Antiochian Patriarchates fell into heresy, Orthodox Patriarchs were elected. Then, was it "technically" possible for Orthodoxy to elect a Patriarch for Rome?