1) Under the Node, Group, App, etc. display ALL preconfigured alerts that meet the conditions in advanced alerts to the Node, App, Component, etc.
2) Allow users to subscribe to individual or ALL alerts indefinitely or for a period of time by Node, Group, App, etc. but still allow the master alert to still apply. This ability could be given in the accounts security.
Example: Alert of 100% CPU of x amount of time alert ServerOperationsTeam@mail.com
Allow a user not in the Server Operations Team email group to manually subscribe to the alert. The user could have just released a new app / update to the node and wants to know if issues arises over a period of time or is just highly interested in a particular Node/App/Group.
This is helpful in many ways:
1) Takes administrative tasks off of the Admins.
2) In large environments with multiple teams and environments this would be very helpful.
3) User's may or may not be inveterately bombarded with unnecessary alerts.
OTHER: You could take it a further and allow the user to see all alerts in a "personal settings" page to see all the alerts they have subscribed to.