Complete collections of recordings occupy an important place in the artist’s heritage and in his discography. In addition to its main purpose - to provide as many artist recordings as possible (generally for a certain period) - such releases contain the most detailed information about recording sessions that is not available in other types of releases.

Here are some examples of such releases:

• Jerry Lee Lewis at Sun Records: The Collected Works ("What the Hell Else Do You Need?")
• Fats Domino - I’ve Been Around: The Complete Imperial & ABC-Paramount Recordings
• Billy Lee Riley - Classic Recordings 1956-1960
• Little Richard - The Specialty Sessions (8 Album Set)

Please pay attention to the booklets (or rather books) of these releases.

Such releases are far from being awarded to all artists, so the very fact of their availability testifies to the worldwide recognition of the artist's merits. Meanwhile, now such releases are simply lost in a long list of hundreds of compilations or at the end of the list of Release groups under the type of "Other", which does not attract the attention they deserve to them.

Even in MetaBrainz community there are people who are not aware of the existence of such releases and the information they provide - see the discussion here.

I propose to add "Complete collection" as a Secondary type of Release group and to place such Release groups ("Album + Complete collection") immediately after "Album", before "Album + Compilation".