This might be outside of Prairie, but at the very least is tangential.
This blog post talks about how Mozilla is creating some new tools to monitor contributor experience and catch people falling away. They are really trying to tackle the same issues that the Prairie Initiative is. Perhaps we can borrow some ideas. Here is a quote from the blog post, but I've replaced "Mozilla" with "Drupal":
My own feeling is that within the Drupal community the products, like Drupal Core, evolve quickly, but the process by which people work together tends to evolve more slowly. This is a problem. If Drupal cannot evolve and adopt new approaches with sufficient speed then potential and current contributors may go where the experience is better and, over time, the innovation and release cycle could itself cease to be competitive.
This task is made all the more complicated since Drupal's ability to fulfill its mission and compete against larger, better funded competitors depends on its capacity to tap into a large pool of social capital - a corps of paid and unpaid coders whose creativity can foster new features and ideas. Competing at this level requires Drupal to provide processes and tools that can effectively harness and coordinate that energy at minimal cost to both contributors and the organization.