The auditing system within Orion works very well, allowing us to track most of the who did what and when kind of queries that I am ask for..
However, once a node is deleted from the system, all generic data is lost.
For us it would be very handy to keep some basic details, of the deleted node, such as its name, ip address, maybe a few custom properties and the notes that have been added to that node.
This would also mean that when a user deletes a device, the ticket reference can be added to the notes, making tracking down why a device has been deleted, so much easier (which we could then extract out into the CMDB).
The deleted status would be similar to unmanaged, except the historical performance data would be deleted from the DB.
A threshold could then be set, to remove the deleted devices entirely from the DB after X weeks, months, years.