Believe me, there was a lot of discussion on this subject for the first decades of the history of jazz.
We balanced from using chronologically sequenced collections (like the Classics), complete collections recorded for a label from a period (like a "Complete XXX-Label 19xx-19xx recordings") or compilations with a maximum covered period of 10 years (Hawkins was in another league for the high average quality of his vast and chronologically extended recorded output).
And we ended up using... all of them.
In each case we analized multiple factors (from sound quality and remastering, to easy availability or representativity of a period of that artist). If there was a body of recordings such as Ellington´s RCA Blanton-Webster band or Satchmo´s Hot 5&7, so absolutely essential all in all, we picked a more than 1 CD collection. If there was a single chronological disc containing such ammount of master works from an artist to be representative enough, we took it (i.e. Lion´s Classics disc). As for compilations such as Hawkins´, Bessie´s, Django´s or Billie´s, we cared so much for the accuracy of the tracks selected.
There´s a lot of work in a project like this... if it´s faced seriously. It´s easy to list 25+40 good jazz recordings (all of us can do it in fifteen minutes). But it´s not so easy if the compilation takes into account a lot of facts (balance between artists, styles and decades, sound quality, package and liner notes, availability).
Just a clue on how we faced it: it took us three or four months of work and discussion and about 700 emails.
Of course you could have chosen different discs. Jazz is diversity.
Best wishes,
Agustín Pérez