Blessings Gary,
 
I have not followed this movement real close, but I see what they are trying to do.  I commend their attempt to tear down institutionalism and government, yet I think they have fundamental flaws in their reasoning. 
 
Of course there were home churches in the first century:
 

Colossians 4:15 Salute the brethren which are in Laodicea, and Nymphas, and the church which is in his house.

 
Yet, this was driven by several circumstances.  Firstly, small beginnings;  Many churches start in homes as Bible studies even today. Why?  Because they only have a few people. Similarly, many church in the New Testament started in extended families:
 
1 Cor 16:15 I beseech you, brethren, (ye know the house of Stephanas, that it is the firstfruits of Achaia, and that they have addicted themselves to the ministry of the saints,)16 That ye submit yourselves unto such, and to every one that helpeth with us, and laboureth.
 
The household of Stephanas was the "firstfruits" of Achaia, and likely started as a small gathering of family members who had converted to Christianity.  But surely it grew beyond the household of Stephanas, and therefore more structure arose, as well as the submission to the authority within that structure (v16).
 
Secondly, the reason many churches were small is because they were under severe persecution:
 
Acts 12:1 Now about that time Herod the king stretched forth his hands to vex certain of the church.
 
The Christians held private meetings (as they do in persecuted nations today) in order to avoid trouble.  But was this the optimal situation?  Surely the lack of accountability could have had a part to play in the excessive amount of false doctrines (e.g. gnosticism, Judaizers) that permeated the church early on, and which Peter, Paul, and John spent so much time chastizing and warning Christians of.  It was only in a larger, joint session where important doctrinal issues were decided on (e.g. Acts 15 -- Council in Jerusalem).  In fact, it wasn't until after the toleration of Christianity under the reign of Constantine that the Christians could finally meet in larger groups and hash out the critical tenets of Christianity -- the canon of scripture, the Trinity, the deity of Jesus, etc.  If the house church movement despises such gatherings, they better question the canonicity of the very Bible they are reading because it was that very structure that the Holy Spirit used to bring the church into a consensus regarding it.
 
On the flip side, there is danger in churches getting too large and structured, such that they lose the critical aspects of body life demonstrated in Acts 2:42-44.  Large churches should have small groups to facilitate such an environment while residing in a sphere of accountability to the larger body. In addition, all churches should have a plurality of elders (bishops w/ pastoral gifting):
 
James 5:14 Is any sick among you? let him call for the elders of the church; and let them pray over him, anointing him with oil in the name of the Lord:
 
Notice James said "elders of the church", not "elders of the churches".  This may mean a senior elder, associate elder(s), youth elder(s), worship elder(s), small group leaders, etc.. Of course a smaller church may not be able to afford to pay all of them.  Nevertheless, they need to be in place.  Otherwise, you have a one man show which is dangerous.  A one man show guarantees no accountability.
 
The hierarchy of authority seems to be revolved around the five fold ministry gifts:  Apostle, Prophet, Evangelist, Pastor, and Teacher (Eph 4:11ff).  All five of these will continue until the church becomes the "perfect man".  Clearly someone anointed in the apostolic gifting (i.e. regional church planting and overseeing) is to be submitted to by the churches he establishes (1 Cor 9:5), assuming he is following Christ (1 Cor 11:1). Apostolic figures should direct the appointment of elders.  Paul, as an apostle, had the authority to charge the churches in ordaining elders (Tit 1:5).  He also had authority in the affairs of those elders (e.g. 1 Tim 5:17).  He also gave charges directly to elders.  In Acts 20, he charged the Ephesian "elders" to "feed" (literally 'pastor') the flock as "overseers" (literally 'Bishops') -- see v17 and v28.  I believe that the office of bishop, therefore, is filled by people with the gifting of pastor and a maturity level of "elder".  When I say maturity level, I mean maturity in the faith, not necessarily in age -- "Not a novice, lest being lifted up with pride he fall into the condemnation of the devil." (1 Tim 3:6).  Peter, as an apostle, was also an elder and 'witness of the sufferings of Christ' (1 Pet 5:1) -- in other words, he had been around a while.  So, I agree that 'pastor' is not an office, but a gifting granted to an 'elder' to serve in the office 'Bishop'.  We don't often use the term bishop anymore, unfortunately (or apostle for that matter).  I think the modern day "pastor" is really what Paul would call a "bishop", and regional pastor might be akin to an apostle. 
 
So I would say that there was some hierarchy of apostle over multiple bishops, and then bishops over congregations, and of course apostles in joint cooperation with other apostles (Acts 15:2 -- notice multiple apostles met on the issue).  So the New Testament is littered with authority.  It speaks of small house gatherings, as well as huge council gatherings.  I think the home church movement is trying everything in its power to avoid an authority above the pastoral level.  That's not Biblical.  That's how cults form.