Regarding Viola’s assumption, that in the institutional church the structure should not be reformed or renewed because the structure is the problem. Though I think the structure is a major problem, I also think structure is more a symptom than a source of the problem. Leaving the institutional church to its own devices will not solve the problem. I hold to another solution: remaining in the institutional church as the bold, yet respectful, loyal opposition.
My reasoning is this. If it be true that the persons inside the institutional church are Church and that the Spirit in them in witnessing to their spirits that Jesus is the Christ and the center of our corporate being, then change—including complete reconstruction—is possible (however likely or unlikely). Some first steps are redefining things and positions and removing the business/marketing template.
For example, if we say that the large Sunday gathering is worship and celebration rather than the primary event, then we free that definition (“primary”) for application to smaller gatherings throughout the week. These smaller gatherings would include learning groups, serving groups, and everything in between. If these smaller groups redefined themselves as primarily Christ-centered communities with specific tasks I think, the institutional church would begin to change. Of course, there are some things that must be rebuilt from the ground up. 
I realize even as I say this, that those who are fully committed to organic or house church will likely consider this a compromise. And indeed it may be, but I think the community of persons inside the institutional church is worth it.
 One thing that we must change is the solo senior pastorate being one (which I believe to be unbiblical and wrong). We need a plurality of elders (“older holy one”) who really do lead—stepping out there first, putting themselves on the line, and living lives that look so much like Jesus that we cannot help but follow.
Related post: Among the Loyal Dissatisfied