Going down the Tree.
Once you accept Christianity, you have to ask whether you are going to recognize Messianic Christianity or only what we consider the Church.
The first main problem with the Messianics is that they are separate from the Orthodox Church. That is, we are not in communion.
A second problem is that typically they follow Protestant theology. This is not always the case as there are "Hebrew Catholics". But there are few who follow Orthodox theology, although a small number. There is a modern "Nazarene" group, one of whose members was here.
The third main problem is the issue of whether Jewish Christians should follow a different set of rituals and rules than other Christians. One may tend to see it as problematic in that we are to be one in Christ. It's true that women are supposed to wear veils and stand on opposite sides of the church (especially in conservative ones), and we have gender based monasteries. Women cannot be priests, etc. But unlike sex-based divisions, today we have come to reject distinctions based on race. In terms of spirituality, worth, and salvation, Christians are Abraham's sons, for Paul. To deny this would go against the Council of Jerusalem which was the apostle James' decision.
I think the New Testament does not say Jews should or should not practice different rituals than other Christians. So for me it is a small question. However, Christ did give an example of disregarding Mosaic rituals like the idea of ritual cleanliness, which went against touching the sick. In Peter's vision God told him that eating anything was not unclean. I think Paul's idea of disregarding the ritual rules, putting grace instead of law, was not something he made up but what he learned from the other apostles.
So I have to go with the Church based on the three reasons above, although it might be helpful if someone could show me something more on point from the Old Testament or gospels showing that Jewish Christians should no longer do separate rituals.
As for the Arians and Nestorians, I wonder if the differences were really just semantic.
As for the Oriental Orthodox, I have trouble seeing whether the issue of Christ's natures rises to the level of heresy if both the Church and the OOs see Him as human and divine.
The Church's Chalcedon Council made a normal statement that Christ is in two natures or sets of properties and the OOs misinterpreted that two mean by extension that he is in two people. However if the 5th Council practically anathematized(?) Cyril's idea that Christ's nature was of two natures, how can I accept either the EO or OO positions? Would that make me a Chalcedonian nonConstantinople II-ian? At least I go farther with the EOs (the 4th Council). Granted, the 5th Council banned "saying" one nature, not thinking it.
Moving along, assuming there is such a thing as apostolic succession, what about the Roman Catholics?
I have a hard time accepting that the guilt of personal sin is passed down. Also I am pretty skeptical about purgatory.
What about a nondenominational vagante group? Couldn't I find one that actually has the right theology, perfect ideas and customs (theoretically speaking), but just doesn't happen to be in apostolic succession?
I guess. Certainly the one with it is better.