There a few unique and helpful things in Stanton's book about smaller churches.
First, considering a church's unique vocation is significant. Stanton critiques approaches to evaluating church life that focus exclusively on bringing new people in through evangelism. I think he is a bit too pointed, but it's a fine point to make. Even more important is that church's consider themselves as failures if their faithful labors don't result in numerical growth. Considering a congregation's vocation given their make-up, time, and place, is a very helpful idea in leading a congregation and in a congregations own self-evaluation.
Second, Stanton makes regular reference to the work of Richard Thaler and the field of behavioral economics. Namely, we aren't as rational as we think we are. I think this point is epistemologically significant and true. This makes for interesting analyses. Thus, pastors/leaders should not proceed in purely logical or analytical ways, but must lead relationally. A nice point. But this analysis was a bit overdrawn, appearing in at least 3 or 4 chapters.
His discussion about small, aging congregations was helpful.
My main criticism is his construal of evangelism as including nearly everything but proselytizing. It's nice to define evangelism as discipleship and important that he acknowledged that it's the process of a person becoming a Christian. But as much as I think we shouldn't define our success purely on numbers, I do think congregations should always be thinking about reaching the lost with the gospel. That certainly is not the only thing we should do, and its tragic that evangelism is divorced from discipleship and discipleship is often divorced from pursuing forms of social justice.
I think Stanton's book is most helpful in introducing smaller congregations to minister's in training or to minister's being called to a small church and who lack experience there. I wish there was more written about the strengths of small or the yet more audacious claim that small- to medium-sized congregations ought to be more regular. I think most editors wouldn't let you take such a bold swipe at large and megachurches. But I think that case needs to be made.