I’ve got a bunch of sensors that are on a card, via auto-entities, so that they only show up when valid. Unfortunately the state and attributes are fairly ugly natively, but can be cleaned up easily in a template.
So now I’ve either got to have a card that shows sensors when invalid, so that I can incorporate other templated sensors to prettify it … or resort to creating a new sensor, based on the originals, in python. Both methods are a bit hairy and they wouldn’t be necessary with template attributes for template sensors.