In order to view the aggregates in the cluster with the most space, you could use this user input query for the $aggregate variable :
You can also anidate this query to another database to also get the node name, like with this query:
aggregate.name as 'aggregate_name',
cm_storage.node as node,
cm_storage.aggregate as aggregate
aggregate.node_id = node.id
This query can be used in a dropdown but also for a filter/finder to automatically choose an aggregate ( those filters already exist ).
Hope that helps.