Allow "Variable" to be associated with a data field

It would great if you could define within the Data Tab, variables associated with field. The reference the variable in Page>Form> Record Rule.

E.g I have a field Artshow - which has two variables. (Current_Artshow=POPART; Next_Artshow=DADA)

Then I have a table PLAN which includes Artshow.

When adding a PLAN item via a form, the record could automatically populate the Artshow value from a record rule that updates the record.

In addition to custom, form and connected value, the developer could select to a variable value and then have the option to select Current_Artshow or Next_Artshow. By selecting update record value for Artshow with Next_Artshow, the value of DADA would be populated.

Alternative, just a text area where variables could be maintained. Currently, I have record rules that update certain fixed values throughout the application. It would be great if these could be maintained in one place. E.g "contact email address", where you want to include a suppport contact for users. If a person changes, you could just maintain this in one place.