DHK, while you make a great case for the word usage of the NT, you do not explain why St. Timothy, who was placed in charge of a church by St. Paul, then writes to St. Paul for guidance in matters and St. Paul responds to him. If there was no hierarchy as you clam, then St. Timothy would have been on his own and felt no need to write St. Paul in the first place.
Likewise, there would have been no meeting of the Apostles in Jerusalem over the Judiazers issue and no letter sent to all the churches if there in fact were not a hierarchy in the early church.
		
		
	 
Here is the first instance of Paul meeting Timothy:
Then came he to Derbe and Lystra: and, behold, a certain disciple was there, named Timotheus, the son of a certain woman, which was a Jewess, and believed; but his father was a Greek: Which was well reported of by the brethren that were at Lystra and Iconium. Him would Paul have to go forth with him; and took and circumcised him because of the Jews which were in those quarters: for they knew all that his father was a Greek. 
(Act 16:1-3)
--At this time he was a young man and now entering into the ministry he accompanied Paul on his missionary travels. He learned much from Paul, as Paul discipled him. 
In fact when Paul writes to him in his first epistle he calls Timothy his "son in the faith."
1 Timothy 1:2 Unto Timothy, 
my own son in the faith: Grace, mercy, and peace, from God our Father and Jesus Christ our Lord.
--Paul was like Timothy's spiritual father. Timothy was a very young man, and Paul had become "the aged apostle," who had much to share and teach this young man. Paul encouraged Timothy:
1 Timothy 4:12 
Let no man despise thy youth; but be thou an example of the believers, in word, in conversation, in charity, in spirit, in faith, in purity.
--Simply because he was young that shouldn't be a hindrance for him in serving the Lord. 
The spiritual principle that Timothy was to follow is stated here:
2 Timothy 2:2 And the things that thou hast heard of me among many witnesses, the same commit thou to faithful men, who shall be able to teach others also.
--This is spiritual reproduction. Timothy was to teach faithful men, who in turn would teach other faithful men, etc. This is how we operate. It is how another pastor is trained and another church is started. 
Faithful men teaching faithful men. 
As Paul was as a father to Timothy in the faith, it was only natural for Timothy to seek him out for guidance. They had worked together, lived together, traveled together, suffered together. Paul had discipled him. 
You will notice the same pattern in the Corinthian church. Paul spent 18 months in Corinth building that church (the believers, not a building). He put his life into it. When he left he put Apollos in charge. Some time later he received a letter from the church with a number of questions concerning problems that were in the church, and that is the 1 epistle to the Corinthians, Paul answering those problems:
1 Corinthians 7:1 
Now concerning the things whereof ye wrote unto me: It is good for a man not to touch a woman.
--Just the first part of this verse: "concerning the things your wrote to me." They had written him a letter. He is answering it. 
In chapter five, he is astounded by the immorality that they have allowed and gives them some very stern instruction, that they were to carry out, not him.
1Co 5:1  It is reported commonly that there is fornication among you, and such fornication as is not so much as named among the Gentiles, that one should have his father's wife. 
1Co 5:2  And ye are puffed up, and have not rather mourned, that he that hath done this deed might be taken away from among you. 
1Co 5:3  For I verily, as absent in body, but present in spirit, have judged already, as though I were present, concerning him that hath so done this deed, 
1Co 5:4  In the name of our Lord Jesus Christ, when ye are gathered together, and my spirit, with the power of our Lord Jesus Christ, 
1Co 5:5  To deliver such an one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus. 
In both cases Paul was not the Pope, the bishop over the area, etc. There was no hierarchy. In Timothy's case he was as a father to him. There was a great difference in age and a very close relationship.
With the Corinthian church, Paul himself had founded the church. He knew the people. They still looked to him as the founder, the original leader and even pastor. There were as many as four epistles to the Corinthians that Paul had written. Only two were inspired Scripture. 
Concerning the Judaizers, they followed Paul wherever he went stirring up trouble wherever he went. The entire epistle to the Galatians is written to counter this poisonous doctrine. He calls it "another gospel," and calls those that preach it "accursed." (1:8). 
He refers to in his epistle to the Colossians. 
Acts 18:12 And when Gallio was the deputy of Achaia, the Jews made insurrection with one accord against Paul, and brought him to the judgment seat,
13 Saying, This fellow persuadeth men to worship God contrary to the law.
--These were Judaizers here as well with the accusation "contrary to the law," the Jewish law. 
This incident happened well after the "council" of chapter 15. It happened throughout Paul's life. They never gave up their cause. The decision at Jerusalem did not settle it just like Council of Nicea did not settle the matter of the Trinity for the United Pentecostals, and many others that still do not believe the trinity.