It would be real handy to be add the ability to include / exclude entities for inclusion by label, in addition to entity name, domain, etc. as is implemented in EntityFilter.
Consider the recorder database, or external storage like in InfluxDB. Today, I exclude entire domains and some globs from being stored. It would be handy to be able to annotate individual entities of a device with some label to enable them to be acted upon. This means that I could fiddle around while setting up a new device, renaming entities, etc. and not inadvertently emitting updates that create some new series in InfluxDB or otherwise create some soon-to-be abandoned data after renaming occurs.
Only once the dust has settled, I could add the applicable labels that matched the filtering configuration of the recorder db, or influxdb, etc. that might each have their own label.
This also would also aggregate the state for how the data associated with an entity in one place (as labels), rather than being scattered arcoss different part of the Home Assistant configuration.
I would suggest adding a labels list to the existing entities, entity_globs and domains strings/lists under include/exclude maps.