Hi Gregory.
No problems - we have to ask to get answers, then we have to weigh them. I'll offer a few thoughts on a few of your questions regarding Scripture and the early Church at least. That part of history I'll leave to others.
You're right that context is important. That's where the understanding of the Body that received Scripture (before it was Scripture) can help. After all, Paul refers to himself as Timothy's father, and says that we have many teachers but not many fathers. So with no understanding, we'd have a contradiction in Scripture.
We are not to call anyone Father, Teacher, etc. as an extreme honorific. If it's meant to kind of show them as being far above us, it's done wrongly. The "Fathers" in the right context are like actual fathers - they use their wisdom to guide, they protect as they can, they pray for and take care of their sons and daughters, they bear their burdens, suffer over them, serve them. Yes, they are leaders in a sense, but not dictatorial ones. Servants to all, in a sense. I'm not sure if that helps. But if you accept all of Scripture, you have to see that "Father" is not always a forbidden term.
As far as what Catholics might believe, I'm not sure. The priest never "becomes Christ" for us. He does fulfill a priestly role, which the ultimate High Priest is of course Jesus.
We do also have the Sacrament of Confession. The early Church also practiced Confession (generally not privately) ... Jesus did give authority to the Apostles to release or retain sins. BUT ... I want to say that we consider the priest to be only a witness. It is Christ we actually confess to, and Christ who forgives. If a person came to Confession and secretly planned to go right on sinning afterwards, the priest might believe him repentant and might read the prayers that say he is forgiven - but God knows the heart and that is ultimately what matters.
We do have a direct line to God.
That is always available. But the word "pray" has changed its meaning over time, which causes confusion.
To pray used to be simply a request. You know the older English? "Pray tell, when will the doctor return?" It's not Worship or any such thing - just a request.
Prayers to the Saints are simply asking them to pray for us, much the same as you might ask your pastor or your very godly grandmother to pray for you. We know that "the effectual fervent prayer of a godly man availeth much" ... and who is more godly and effectual than people who love us and are already beyond the temptation and struggle of this life and are now in the presence of Jesus?
Usually there is a question about how or if they can hear us, and whether that is trying to communicate with the dead. The answer is that we do NOT seek to bring them up or converse with them or get them to answer. That would be beyond foolish! (And possibly a demon might offer to trick us!) But they are not omniscient. Like the souls of the martyrs under the throne in Revelation who ask about God's response to what they know is happening on earth, the Saints in heaven only know what they know because they are in communion with Jesus -- and He knows everything.
I hope you don't mind me replying btw. It's just something I enjoy. And if it can help, I'm glad.
We don't pray the Rosary. There are some things about the Rosary (that I've heard) that are taught against by the early Desert Fathers (like imagining certain things during prayer). We usually don't repeat a lot of prayers - mostly prayers are said once during a prayer session except for short phrases like "Glory to the Father and the Son and the Holy Spirit" which might be repeated between other prayers.
An exception is the Jesus Prayer, but that would take a whole lot more to explain. Not everyone prays it, and not everyone who prays it does so with the intention it is supposed to do - very basically it is to teach us to remember God all the time - always - and to teach the heart to pray all the time - unceasing prayer.
But that's really quite different from the Rosary.
Catholics have various things (I'm not sure how widely believed or practiced) that a Rosary can be prayed for a person based on so many days or so many times, just as they sometimes have other actions or prayers they do x-number of times or at certain times - this theology tends to be connected to their doctrine of purgatory or the Catholic idea that all sins require temporal punishment, or are connected to "graces" God gives, but we also don't believe in measured grace or grace as a "thing" ... rather it is the energies of God through which He interacts with mankind.
Anyway. My little attempts to help. Forgive me if anything I've said makes it worse, and feel free to ask further if I've made it more confused or brought up other questions.
God be with you.