As far as the filoque, I believe (correct me if someone can actually provide a source) that St Maximos the Confessor basically iterated that the Latin understanding of the filioque was permissible in the Latin version of the Creed but not in the Greek (this is the modern standard defense). Of course Maximos would side with the Pope as long as he was not in error, given that is where he went to try to get the monothelite heresy resolved.
St John of Damascus says (based on the Cappadocians) that the property of the Holy Spirit is procession. However, the Holy Spirit processes from the Father (as Cause and Emitter) through the Son (as communicator).
None of the Fathers would doubt the purity and sinlessness of the Theotokos (which is not a question among the Orthodox until after 1858, after the Dogma of the Immaculate Conception was declared).
The idea of Papal infallibility is the real question. It seems to be an idea that grows throughout the Middle Ages, but is generally theologumena until Vatican I. Even then, I am not sure it is well defined from a contextual perspective since the council did not complete its work (not by a long shot). Generally I have understood it as being a very narrow set of extraordinary circumstances and conditions in which it applies (this is certainly how Pius XII and John XXIII approached it). The Primacy of the Pope of Rome was certainly not debated by the Fathers. We have plenty of cases where they appealed to the Pope for relief in their own circumstances. I think it is a matter of degree. Would they think the Pope has ordinary jurisdiction over every Christian? No, I don't think that level of authority would even enter their minds. It is a question that is really only possible given the immediacy that technology has given us to what the Pope says or does. To most people, the authority of their priest and bishop mattered. to the local priests and bishops, their metropolitan, to the metropolitans the archbishops, to the archbishops the Patriarchs. There just wasn't access across levels of hierarchy then as there is today. So this is a new problem we have to sort out.
