I don't see how this is answerable without knowing the terms under which we have managed to unite. I mean the only realistic terms anyone has managed to come up with up to now are basically submission to the other side (Orthodox accept Papal 'univeral ordinary authority' and 'infallibility' or Rome dropping everything they've added in the last millennium) and each of those leads to some different answers. A third option, one actually acceptable to both sides, would presumably lead to a 3rd answer--but without any idea of the shape of that option, how can we know what it would result in.
There is a different approach. I would mean that papal primacy and supremacy be clarified so that we don't have a situation where al Misry and witega get to tell the rest of us what papal primacy and supremacy means, with elijahmaria jumping in ever few posts to say "Bunko!!" I think that would be useful.
In the process of doing that it may be apparent to all that papal authority is an authority of service and unity.
Even now, in the west, the papal office is faced with eastern Catholic primates who do not yield one bit of their jurisdictional authority, and so far it has not been demanded of them.
So one might grimace at all that has been done that is awful and abusive...yes. But that need not follow into the future. We are capable of learning from our mistakes.
And we do have examples of primatial and papal power and authority operating in peaceful synergy.
So to me, the idea of resuming communion would mean that very little changes in Orthodoxy...in fact nothing at all changes in the operations of the various jurisdictions.
Rome would yield the Paschal calendar to the Orthodox and the Catholics would simply begin celebrating Pascha with the Orthodox.
You could go from here adding details.