Maintenance Mode Exit Health status not a New state change
When SCOM enters maintenance mode and then exits it will re-examine the health of objects and re-discover issues that have already been raised previously - causing more alerts. It should check previous state before maintenance and not re-alert for something that has not changed. Alternatively if the state of alert is changed to something like "Acknowledged" then it should not keep alerting or appearing as a "New" state change.
I'm curious how this would affect Monitors and the ability of monitors automatically closing alerts. I'm under the impression that exiting MM also resets the health of monitors which causes this behavior. Fix the fact that some monitors require a forced reset to change their state. Exiting MM should never result in more alerts if the alert has already been generated.
At least make it a choice.