You are confusing theology with ecclesiology. The Presbyterians and Episcopalians could never sing off on theology. That's what matters.
The EOC is run the way it was run from the beginning. It was the Latin Church which "evolved" into this pay-pray-and-obey organization. I believe it was +Cyprian who argued for the Eastern ecclesial model and lost. The West simply became too Frankish.
But that's not the Orthodox concern as long as any reunion does not imply Latin ecclesiology. The reunion hinges on the profession of the same faith and the undertsanidng that both Latin and Orthodox traditions express identical cocnepts in different words. So far, no one has been able to show that different woprds mean the same concepts, which is why there is no reunion.