Doesn't seem like it's possible to leverage the "database" storage option in a provider-inheritance configuration.  It appears that the child project areas that inherit the enumeration set to database storage can properly see the enumeration and they have the expected ability to add new literals, but when the work item is saved the new literal is not saved to the process config.  Where-as when done in the process provider project area, the enumerated list is modified in the configuration as expected with the new literal values and new work items see all the literals as expected as well.

Is it possible to set up Fine-grained Customization of Configuration Data, specifically enumeration attributes (either just new literals or entire enumerations) in inheriting project areas and have the storage set to "Database" so the literals can be added from work items?

I can see not variable in the Fine-grained Customization of Configuration Data wiki where one can even specify database storage on a new enumeration defined in the inheriting project area.

The issue is in setting the override in the process inheriting project area for enumerations will disconnect that section of the process configuration from the provider from that point forward.  That is a heavy consequence and why my customer prefers use of the Fine-grained Customization of Configuration Data where possible.

The issue of having to manage solely from the process xml in the inheriting project area might be ok.