In the Notifications feature, it would be really helpful if you could send a test notification when you set up a new email. Currently, when you set up notifications it isn't clear if they work. This is especially important for integrating with other services.
For example, I set up the PagerDuty email integration and added the email address to the Notifications list, but it's not clear that the integration is working right now. In fact, I won't know it's working until:
1. Something fails and we get alerts
2. Something fails, we don't get alerts, and we realize we should have gotten alerts
The second scenario is potentially very dangerous because it gives a false sense of security. There is a good chance that you never realize that you were missing an alert so you'll never fix the integration.