Who do I talk to about redistributing our iCloud storage among family members?

No one. You can add family members to the family sharing group to share storage on your own.

Devices are not specifically added to iCloud Storage sharing.

You invite Apple IDs of the people that own the devices, and any devices signed into those Apple IDs can then access the shared storage.

See here to invite members to the Family Sharing group to share iCloud Storage: link-> Share iCloud+ with your family - Apple Support

To share an iCloud storage plan with family members, see the information in the following article from Apple: Share iCloud+ with your family - Apple Support

Note that you cannot distribute or allocate how much storage each family member has; every family member has access to any unused storage in the shared plan.