Shared realms configuration

Hi all!
We are using multi-tenancy implemented as realm per tenant.
Tenants share same client configuration, realms settings, roles.
Applying same configurations changes in all realms is a tedious, error-prone task.
Exporting and importing settings as json files is helping a bit, but it doesn’t seem a long-term solution.

Could you please point me to an idea how to do that effectively?

What I think about is Realm SPI implementation which will point on a virtual realm - let’s call it ‘base realm’ - which will only exist to provide base configuration. Is there any other mechanism of such an inheritance of realms. Maybe there is something more smart than that available?