We've had a year with the software and are about to renew. By and large it's been a great experience. This is an exceptionally complete membership management solution. You've taken some of my suggestions in the past. Here's one which I think I might be useful to other users.
By default we can send three e-mail reminders to subscribers. My client has had a leadership change. The new boss would like to be able to send more reminders. I think he would prefer the option of five or six. I can see how clients might want the option of more reminders. Then they want to choose exactly how many reminders via the general config parameters. Let the admin choose three, four, five or six reminders. Since you already have the basic infrastructure developed, I would hope that expanding it would not be too difficult. We would happy to be the early adopters for the purpose of developing this further. I think it might add more utility to an app which already has outstanding flexibility.