A client is using AEM and wants to make sure they are managing their configurations...

A client is using AEM and wants to make sure they are managing their configurations correctly. Refer to the following requirements:

The client has multiple brands that they will be hosting on a single AEM implementation

The client wants to reuse as much between brands as possible

Each brand needs to be able to override the default values for items like contact us information

The client plans to support multiple languages in multiple regions for each brand

Each brand/language/region combination will have its own set of content approvers used as part of a custom workflow

Which approach should an Architect recommend to manage the client's configurations for AEM?