I'm looking forward to talking about all this when we get together, Jess! But since you asked, I'll give a bit of a summary here and now...
First, my wife and I are super-excited for the transition God's been leading us toward and clarifying during these past 8 months. Our growing convictions and application-move is tied to our obedience to His leadership. As we diligently seek Him individiually and in community, we trust that we're walking only as He leads and are more than willing to redirect in any way if He makes a different desire for us clear.
Also, as we follow God's leadership and rest in Christ amidst all this, we're happy to understand our transition not as "leaving the local church" but rather as rejoining it. I've come to understand a local church as a community of Christ-followers caught up together in a common Spirit (a universal reality), as well as a common geography, cultural identity, relational network, and mission. Our move to Arizona is actually a move into that reality and thus into the local church.
As I continue to study and observe, I'm actually growing inclined to suggest that it is the institutionally centralized eccelsiological method that has left the local church. The culture traditional-institutional models foster in the West are (in general) cultures of consumerism, limited or contrived community, passivity in personal disciple-making, & resistance to personal responsibility in spreading Christ's Kingdom justice to the oppressed. This culture bears striking resemblance to secular culture and stands in overwhelming contrast to Christ's Kingdom culture, which He demonstrated and taught while on earth.
We believe, as stewards of Christ's "ministry of reconciliation", we are called to abandon the disconnected lifestyle both authoritarian and democratic cultures produce and commit ourselves to following Christ into a connected lifestyle. By "connected" I mean reconciled... as in, reconciled to God (2 Cor 5:18), to the saints (despite ethnicity Eph 2:14), to our neighbors and ourselves (Mk 12:31), to the lost, to our mission (Gen 1:28; Mt 28:18-20) & to all of God's creation which He smiles on (e.g. environment, animals, ecological systems, etc.) (1 Cor 15:28).
It's about calling people to live in Christ's Kingdom culture, a biblically prescribed culture, an incarnational culture... a connected culture wherein people are fully surrendered to be led and empowered by His Spirit. It's a culture in which "normal" living is living that is actively, relationally connected to God's person and work in, through, & all around us. Traditional-institutional "church" methodology, while producing some praiseworthy results in many Kingdom categories, inherently limits the full reality of this culture. The troubling thing about it all is that many Western Christians are so inculturated in lifestyles of independence and consumerism that they don't even consciously know they're missing the majority of God's Spirit and Kingdom in their living experience.
So the question we ask isn't, "Why are we leaving the institutional method?" but rather, "Why would we hold onto it?" We still intend on gathering with the saints, corporate worship, the Sacraments, studying the Word, preaching an incarnational Gospel to the lost and relationally discipling the saved. We even still recognize the great need for better and more Christian institutions (especially local) with clearly defined missional identities (e.g. Compassion, Food for the Hungry, etc.). The notion of living in the footsteps and according the words of Christ and experiencing all of the life He offers to us on this side of glory while avoiding the obstacles we believe are inherent in the impersonal institutional entities that errantly call themselves "church", is a very attractive one we hope the whole body of Christ will be enraptured by.
A couple of starting books by traditionally popular authors that express more of the reasons behind my conclusions on Western and Western-Christian culture include The Connecting Church, by Frazee and Revolution, by Barna.