Again, I must say it was a pleasure to read your article. Thank you.
Here are my thoughts:
The crux of the issue here is: What is the best acceptable model of governance for the church / congregation?
The problem with the interpretations of Acts 15 and a supposed "governing body" fuctioning in the first century (I think there was one, but that's besides the point of the considerations I'm going to discuss now), is the legitimation of the current model of governance in place among the Jehovah's Witnesses.
Back in the 1970's, the majority of the members of the board of directors of the Watchtower Society - much against the opinion of Nathan knorr and Frederick Fraz, who even said that the creation of a Governing Body would only be done 'over his dead body' [boy, was he right!] - decided that there should be a "Governing Body" to govern the organization, rather than the power being concentrated in a single person [the President of the WTS] and then partially abrogated to a board of directors, organized in specialized comitees. How does one justify and legitimate such a change in JW land? In the best JW tradition, the Bible can be bent to say whatever the leadership wants it to say, and the justification for a model of 'theocratic governance' in the shape of a "Governing Body" isn't actually too far-fetched, biblically speaking.
In the early days of the International Bibe Students, the operational model of organization was a mix of elements taken from congregational and presbyterian traditions, and thus, a model that allowed each congregation a great latitude of operational autonomy, while the doctrine-making was centralized in Russell and his close associates in Allegheny, and later, Brooklyn. However, when J. F. Rutherford forcefully took over the WTS, the model began to change. The new implemented model was now much more hierarchy-dependant, and much more under strict operational and doctrinal control of the Watchtower Society, through their appointed representatives, District and Circuit Overseers, and then even the body of Elders became appointed through direct supervision of the Branch office. The model was now typically episcopal in nature, similar to that of the Catholic Church. The President of the WTS was, for all purposes, the JW's equivalent to the Pope. All these changes were justified using the Bible.
Problem is: That we know of, Christ didn't spend much of his ministry organizing the church. Aside from appointing the 12 apostles and giving Peter a measure of evidence among them, there isn't any other hint in his words of how the church should be organized, both in operational or in doctrinal terms. If the aspect of how the church was to be organized was crucial for the evolution of Christianity, isn't it obvious that Jesus would dedicate a significant portion of his ministry to train his disciples to run an organized church? Wouldn't he leave behind a set of instructions on how a church should be organized? Truth is, he didn't. The "head of the congregation" didn't do that. We may then conclude that he allowed his disciples a degree of freedom to organize the church in ways that would favor the expansion of Christianity, and the Holy Spirit would bless all the ensuing efforts. The early church was organized around the authority of the 12 apostles, but then came Paul, who was empowered to be an apostle directly by Christ. This comes to show that, if there's anything that Christ was at this point, he was a disruptive force towards a concept of ecclesiastical power centralized in Jerusalem.
If, then, the concept of a "Governing Body" centralized in Jerusalem was at best no more than a temporary arrangement who couldn't have existed in Jerusalem beyond 66 CE, we can ask ourselves: Are we in anyway bound to the vague organizational model of a "Governing Body" that might have existed for a while, but was by no means an arrangement that should be perpetuated in time? Does modern church need to find legitimacy in the Bible for its organizational model, or should it just be what is more practical, more inclusive, more efficient, while respecting the principle that Christ is the real leader of the Christian congregation?
I believe that the issue of how the church is organized nowadays shouldn't be bound to the way it was done in the first century. We simply don't have enough elements to make definite assumptions, nor can we conclude that the early church was properly organized in a unified way.