Your last paragraph is very questionable. The OT definitely tells us that if a prophet gives a false prediction, they are false prophets. The prophets in both OT & NT spoke under the inspiration of the Holy Spirit and were free from error. There are not two types of true prophets in Scripture, one's without error and others that are 'capable of error'.
I also do not believe there are true prophets today. Eph 2:20 tells us that the ministry of the Prophet was 'foundational'. Once a structure (Church) is erected, there is no need to re-build a foundation again. The Church no longer needs prophetic revelation in the person of prophets as we have God's final revelation in the completed canon of Scripture
Yes, this is all questionable to me, as well, as I indicated from the start. I hold my current positions because I've witnessed prophecies from those like David Wilkerson, John Jackson, and Kim Clement give utterly amazing true prophecies.
The Vision had amazing fulfillments, even if some remain unfulfilled. The same could be said for the Perfect Storm and for the prophecies of Trump, the "Trumpet." Amazing prophecies that I don't think anybody could anticipate--the fall of the Berlin wall during the Cold War, specifically-identified weather events, and the political rise of Trump appear to be breath-taking in scope.
Were these so-called "prophets" perfect? No, I don't think that even the biblical Prophets were perfect. You can read all about Jeremiah's complaints or Jonah's resistance to obedience in their own books. But biblical books are kept free of questionable doctrine, and are reliably true prophecies.
We read of other men in the Bible who were called "prophets" legitimately, and yet were flawed. There were the prophets who insisted on searching for Elijah's body, and the prophet who misled another prophet to his death. 1 Kings 13; 2 Kings 2.
In the NT, Agabus' prophecy about Paul (Acts 21) was viewed more as a prophetic warning than a deterministic set of events that must happen to Paul. It was recognized that some prophecies were in fact warnings, and not just predictive events, such as Joah's prophecy that Nineveh would be destroyed when it repented and avoided that judgment.
I do agree that early NT prophets worked together with the initial apostles of Christ to establish a foundational doctrine based on Christ as cornerstone of the new spiritual temple of God. But this does not mean, necessarily, that prophets were to be confined to this "foundational" ministry.
Certainly apostles and prophets in the Early Church are to be identified as "foundational" ministries. But confining high leadership such as apostles cannot have been restricted only to the 1st century, and prophets appear to be a regular part of church order according to Paul ini 1 Cor 14.
But it's something we are required to judge, as even Paul said that those who speak in churches must be judged by other leaders. Thank you for your thoughts. My own beliefs are not "set in stone."