I am presuming that it is possible with RapidInformer to send a message when, for example, a new interface is discovered by Smarts on an existing router.
Using a Topology connector, in Listen mode, attached to the IP AM, and with the Topology Class "Interface" ?
make sense ?

monitoring Smarts topology changes with RapidInformer
It certainly is an interesting idea and sounds feasible exactly the way you're describing it.
The only concern may be that there may be too many messages when the connector first starts. Smarts API gives all the objects in the beginning. You may need to store the existing interfaces in the database and do a lookup in the connector and create messages only for new interfaces.