I second the request for some kind of call hunt. It is pretty common to see call forwarding triggered by three conditions: busy, no answer, and always.

Another request is something I have with a different VoIP provider, and that is the ability to create and apply time schedules. The idea is that on one page you create and name various time schedules: e.g., "Class" MWF 2:00 p.m. - 4:00 p.m., or "Vacation" May 25-May 29. Then you can use these schedules in connection with other features such as call forwarding, routing, do not disturb, etc.

Together, these features would offer a lot of flexibility and power: e.g., I'll be in a series of meetings and conference calls the week of May 25 between 2:00 and 4:00, but I need calls from a particular group of individuals to reach me on a specific back line, while a different group of individuals get a busy signal.

If these suggestions have been made before, I apologize. I haven't seen them.