>>534976061
You could do something like a 'one-of-each' kinda thing?
>Each Girl must be a representative of a race
>No two Girls on the team may share any of the same races
>The more races a Girl has, the more she counts for (ex; if a girl who has dragon/beast/apoptosis as her starting races is on the team, then the team cannot have any other girls who are dragon, beast, or apoptosis as any one of their races)
>No Race Changes are permitted, barring special events
>If a Girl gets a race change from a special event, then it adds to her race count (ex: once Bunny has obtained slime/beast, then she can no longer be used with other slimes or beasts)
>No Main Characters are allowed (Luka, Alice, Ilias, Sonya, the Elemental Spirits, Heavenly Knights, Luka/Alice/Ilias's Family, etc, as well as the Six Ancestors and Seven Archangels, are not permitted to be used)
>Once the Party is down to the final Tier 5 Races, a Girl may only master One Race, and another Girl on the same team may not master that same Race; everyone must have a distinct final Race that they end on
>Optional: The Super Races (Goddess/Dark Goddess/Third Goddess/Apostle/Deus Ex/etc) aren't allowed either

Could either do that or a 'as minimum a number of jobs/proofs as possible"; but if neither of these also work for you then I'm just out of ideas at the moment.
Hope it's able to help you a bit though.