So I wouldn't consider intolerance or resistance to unity to be a trait of converts.
Don't forget those hotbeds of converts (not!) -- Mt. Athos and most other Greek monasteries -- who are overwhelmingly opposed to the idea of union with Rome as things currently stand.
I am wholly opposed to distinguishing "cradle" Orthodox and "converts". There are Orthodox and heterodox, period. Those who are Orthodox in their hearts are Orthodox; the timing of their conversion is irrelevant. Those who are Orthodox only on paper are not Orthodox because their life is not. Our all-merciful God gives us until the last breath to convert; no one is keeping a score when that happens.