1054 is more of a symbolic event, than actually a meaningful one. It did had the same impact than 476 in this regard, as the contemporary people didn't really saw it as a permanant division (by exemple, when they actually searched the excommunication in their archives, Byzantines didn't found it or feigned so).
Basically, without 1054, the Great Schism as many chances to happen than IOTL, and another date would be chosen to mark it.
If you search for a more historical date, 1204 is clearly when Latin and Greek churches definitely split. After the conquest of Greece and Constantinople, Orthodox clergy and population didn't wanted anymore to have ties with Rome : even when the Basileus was kinda forced to join Rome in Council of Florence, it was fought against and sucessfully by Byzantine clergy.
The best way to prevent an irremediable schism is to butterfly away the 4th Crusade taking Constantinople, something not that hard actually : make the byzantines proposition to crusaders in order to use them as an army for their own inner policy (something that wouldn't backfired *at all*), or make more crusaders refusing to take Zara for Venice (many refused, and it wouldn't be that hard to expand the move). As the pope frowned upon such moves, you should have something there.
Now, if you want to prevent the appearance of the doctrinal differences between Latin and Greek rites, the easier is to break the Byzantine Empire. When Latin clergy had a certain autonomy in western Christianity (that went only in expanding, except for the Carolingian era), Greeks had to comply with what you could call a cesaro-papism.
Roman popes, even after the end of Byzantine papacy, remained an important asset in religious conflicts (such as Iconoclasm crisis), so if you manage to weaken Byzantium, or to fracture it enough, you could see a drastic reduction of doctrinal differences.