I know this is really late response but here it goes.
You keep on saying the church is a body of people, which of course, it is. But it is more than that:
It is the depository of truth (1 Tim 3:15), has authority (in bishops and apostles), and makes judgment (Matt 18:17).
It even witnesses to the heavenly places (Eph 3:10). Finally, as I said before, it is a gathering
not a list of names.
Any history can be helpful, but it isn't necessary, as the bible contains all the history we will ever need.
History gives us context to understand. But it is more than that. It is how God works.
We look to each other to learn the scriptures, as the Lord gifts people with wisdom, and teaching abilities, as well as knowledge and understanding---some more than others. Holy Spirit is our ultimate teacher and He is the one who guides us into all truth.
Actually, you don't. You --like all of us-- depend on someone to give the scriptures some context. You have Luther, Calvin
etc. We have John Chrystostom, Basil the Great, Gregory of Naziansus, among many others. The church has figured this all out and passed the wisdom throughout the ages. You have Bill Bright, phrases like "born again" and "personal relationship." That may speak to today, but it is not they spoke historically. (Whether the meaning
of these phrases is historical is a debatable matter).
You say that we, regardless of our size and history, are not really Christians, based on some phrases which are not in the Bible.
Furthermore, while some might have saved by reading the Bible and depending on the Holy Spirit to interpret (as you say above), this is also how heresies (and denominations) develop. We have the history of the Church, which has figured all this
out so we don't repeat the same mistakes.
Finally, you say "the Bible is all you need," but it's not. It's just a cliche. You won't, for example, find the word Trinity or direct references to the Holy Spirit as God, yet you believe them. Beyond that, you have your Protestant fathers who give you
a context to read the Bible.