In our setup of QB we have a great number of resources defined for supporting various build configurations, for dozens of teams that use them. One current problem is that when we want to "deprecate" a resource, there is no clear visibility on who is actually using that resource.

Moreover, if we drop resource count to 0 - the only feedback the team gets is that their builds will be stuck in the queue. With up to 1000 builds in the queue at the time, this get's lost in the noise.

Therefore I suggest 3 improvements:
-A history page for each resource where you can see at a glance which build configurations have run at that resource and when and sorted by "when"
-A better feedback mechanism for when a resource has rc=0 or a build points at a nonexistent resource - this should send a notify to the person that is maintaining the configuration (the person triggering or if it is scheduled, the creator) and raise a well visible visual cue
-It would be great to have also insight into which configs are the heaviest users of a resource, ie be able to sort by "time utilized" in a certain time range.

While these are not mission critical, they would bring great usability value at least in our case and I would guess other large setups as well.