Rob Dover,
I agree the node tree sorted by custom properties is a great primary visual for everyone - however since it does roll up the status color of the grouped nodes I don't understand the value of a nodeid also associating them. Once you have an Orion group(container) for each of these node "groups" (dynamic query based on a field is best) then you can have the best of both worlds - tree hierarchy right down to the node and a map or resource with group names along with group statistics such as availability.
Since I am using both I found I needed a report for any nodes not in any groups to check my dynamic queries and added a report as a resource to the node details page to show group membership - both helped in allowing a node tree but groups for group pages, maps, etc.
Both of the advanced SQL for reports below were adapted from others on Thwack -sorry no memory of who for proper credit :-(
How to identify nodes that are not part of a group
SELECT groupid,
Containers_AlertsAndReportsData.GroupName AS Group_Name,groupstatusname, GroupPercentAvailability, GroupStatusRootCause
FROM
Containers_AlertsAndReportsData
WHERE (Containers_AlertsAndReportsData.GroupMemberName = '${caption}')
order by Containers_AlertsAndReportsData.GroupName