Renewal Strategies and Risk Identification

I am working on refining renewal strategies and adding risk identification and management. We have many different kinds of customers, each with a slightly different renewal process in place. One size will not fit all. I am adding a risk identification and management strategy and know the obvious data driven signs of risk: decreased usage, lack of log in during a defined period of time, removal of a key sponsor from the application.

How do you identify customers at risk and how do you manage them? If you are willing to share I would love to hear it. Any tips and tricks that may not be well known or are surprisingly successful?