One of the big questions concerning "house" churching is the threat of heresy. Is this a legitimate concern? Perhaps. But to the degree that it is, it should also be a concern in churches led by "trained professionals."
If fact, I contend that the threat of heresy in larger churches is greater. How so? Too often, people blindly follow charismatic leaders, often becoming lazy in their own study. Although I won't go into it here, if I needed to I could point to quite a large list of heresies that have come out of either mainline churches or so-called modern-day revivals.
What's the cure for all this? People committed to being knowers and doers of the word (Jms 1:22-25). And then, as knowers and doers, in grace and love stand up for the truth. Proverbs reminds us, "As iron sharpens iron, so one man sharpens another" (Prov 27:17).
Now, let me address one last important issue with a question. Does your organic church expression have a culture of learning and mutual instruction? Consider the humility of Apollos as he received instruction from Priscilla and Aquila.
"Meanwhile a Jew named Apollos, a native of Alexandria, came to Ephesus. He was a learned man, with a thorough knowledge of the Scriptures. He had been instructed in the way of the Lord, and he spoke with great fervor and taught about Jesus accurately, though he knew only the baptism of John. He began to speak boldly in the synagogue. When Priscilla and Aquila heard him, they invited him to their home and explained to him the way of God more adequately" (Acts 18:24-26).
Occasionally, my Christian brothers and sisters seek to instruct me (...and, yes, I do listen). For example, I've added some verbiage under the "video" section in the left-hand column this week because my friend, Lisa, suggested I do so to remind "babes in Christ" that although the content of the videos may be informative, no one should blindly assimilate information without testing it against the Scriptures. Fair enough.
The above example is only one of many...and many, many more to come. Why? Because Christian leadership isn't about being right all the time, it's about modeling humility, seeking truth, and walking with others as fellow disciples of Jesus.