You can fortunately select multiple event types when creating an event notifier, but I think there should be the option to also select at least Regions, maybe Counties too.
Use Case: I'm interested in CITOs in Switzerland, but only in the area near the Austrian border where I can go with public transport very cheaply.
That area is split up between 3-4 regions, so I would need to create multiple notifiers because I'm not interested in far away, more expensive to reach areas.