I use virtual tags for my LH and RH grouping header:
LH is:
This references other custom and virtual tags to give a header that displays:
- 'album artist · album' if a standard album
- 'album artist · album [type]' if a single, EP, Boxed Set or other non-standard album
- 'album' only if a Various Artists compilation
- 'composer [conductor] - album' if a classical music album with a single composer
You could do something similar (and simpler

) with just:
For the RH:
<Release Date> on $First(<Publisher>)
This references other custom and virtual tags to give a header that displays either:
- year
- month year
- day month year
depending on how much of the full release date is known.
You could do something similar with just:
Released: <YYYY> on $First(<Publisher>)