Absolutely! Herein lies the problem with the Protestant approach: they actually believe that any man can understand God by reading the Bible, and thereby formulate a comprehensive theology.
But, in some respects, they are not to blame. In the Bible they read that the Holy Spirit will teach them everything they need to to know, and they assume that this will literally happen by reading the Bible! The only problem is: the Bible says no such thing!
The earliest Church realized that God is, as the Orthodox catechism says, "beyond everything," a supreme Mystery that is not ours to comprehend. The early Church theologians you mention knew their scriptures and their ancient languages better than we do, and they struggled for three centuries before they could define what it is that the Church believes in because the more they looked into the Divine Mystery the more difficult it became to comprehend.
Today, the Church teaching is a sum-total of all the minds the Church produced in the past 2,000 years and, as you say, we are only beginning to scratch the surface, if at all. No single individual can contain that much knowledge by himself, which is probably why Christ left us a community and not a single leader.
And that would be incorrect. What Protestants believe is that ANY man can understand the gift and promise that God gives us with just study of the Bible. NO ONE or any group - even the combined intelligence of EVERYONE who has ever lived - can comprehend the true and infinite nature of God. But the promise He offers is simple, clear, and direct.
You do not need another book, or another person, to understand the very simple promise: trust in the Lord with all your heart, soul, and mind, accept him as your Savior and you will be saved.
That is the foundation of Protestantism. We do not need a church to save us; only Jesus can do that. The church will make you a stronger Christian, but it will NOT make you a Christian. Only Jesus can do that.
We are called to community to spread the Word and to encourage and support each other in our personal relationships with God. That is the point of Acts - that believers living in community will show the love of God, and will support each other. Not that you have to be a member of the community to become a Christian.