Other than Route control profile any other way to maintain notification matrix?

Here is my requirement.. we have an app engine that sends some notification emails. So far requirements were simple.. we defined some security roles by business units and assigned to users. App engine would look for business unit being processed, find appropriate notifications role and send email to users who has that rol e.

Now we have more complex requirements. Our criteria is not going to be just the BU. In addition to BU, we will have to consider location as well but ONLY in some cases. I was thinking of using route control profiles but since in some cases only BU is used and in some cases BU and location both, it will not be possible to use route control profiles unless we maintain route control profiles for all the BU - Location combination.