There certainly is an argument to be made from consensus. Do I take it correctly then that you also accept (for the same reason you outlined above) millennialism
I'm afraid to say that I don't have an opinion on millennialism; I am simply not educated enough on it to have a legitimate one. However, hopefully from my other answers you can see what I'm getting at anyway.
What I'd like you to keep in mind is that I don't believe in the consensus of now (since that would be committing the fallacy of argument ad populum), but I am very interested indeed as to what the very first Christians believed. If there is a subject on which the early church fathers were pretty much unanimous on, we can take from that that's because the apostles made it perfectly clear to them.
I read a study a month or two ago which said that myth tends to creep into cultures a few generations after the source. If we look at the Bible, we see that all the New Testament was written within a few generations of the death of Christ, and it was after that time (circa. AD 200) that heretic gospels such as the Gospel of Thomas started to appear. Thus, it's really those first couple of centuries that I think are really important (not to say that the next few centuries are unimportant by any means)
that women cannot be in the ordained ministry
Hmmm, well this is an interesting one. There are records of women being church leaders relatively early on in Christianity. However, there are also letters which suggest that the early church fathers did not believe that women should be ordained. It's a tough one, and not one I'll commit to either way at this point in time.
that bishops who derive their powers from having been given them by previous bishops are the only valid rulers of congregations
There's no doubt that apostolic succession was pretty much universally accepted in the early church (Although, please note, that doesn't mean that only bishops can be leaders of congregations!). I tried to find the wikipedia link to an article I read a while ago about this, but it's either gone or it was on a different page.
My belief on this is that apostolic succession certainly was true in the early years of Christianity; that there was a lineage which was passed down. Whether that lineage is still going to the modern day Catholic church/Orthodox Church/Anglican Church is another matter and one that I am looking into, and (once again!) not sure on.
Hopefully you get the gist of what I mean about early consensus now.
It could be argued that since those were once the standard in the Christian churches, they must be right always.
Truth doesn't change, brother.
The early Christians believed that the Church was infallible - let me quote Wikipedia:
"The most basic foundation of the Magisterium, the apostolic succession of bishops and their authority as protectors of the faith, was one of the few points that was rarely debated by the Church Fathers. The doctrine was developed by Ignatius of Antioch (and others) in the face of Gnosticism, expounded by others such as Irenaeus, Tertullian, Cyprian, Ambrose, and Augustine, and by the end of the second century AD was universally accepted by the bishops."
In fairness, Wikipedia also says:
"However, this understanding was not universally accepted. One of the most famous critics of the episcopal corruption was the influential theologian Origen. Throughout his life, many of Origens writings were considered to be questionably orthodox, and he seemed to espouse the idea of a teaching authority based on theological expertise rather than, or at least along with, apostolic succession."
... But Origen was writing in the early third century - about that sort of time which those heretical gospels I mentioned earlier started to appear. The opinion of those who were very early fathers is clear.
So, if the Church declared something then, it's true now. That's consistent with 1 Timothy 3:15, which declares the Church as the pillar and foundation of truth.
Note: I'm not a Catholic, although I am looking into Catholicism and there's an outside chance I could convert. But I don't see how anyone could deny the unanimous writings of church leaders writing at the same time as the books of the New Testament were written
(BTW, it is not true that freewill was the only accepted POV for the first 1500 years.)
I'll give you that not all Christians strictly believed in free will - I believe St Augustus had some sort of opinion on election - but as far as I'm aware, no Christian believed in the sort of predestination which Calvinists adhere to. Within the first few centuries, I do not know of any reference to predestination; certainly not any reference without
also incorporating free will.