A recurring theme in NERS voting is the ability to maintain Premium Sandbox Configuration changes on refresh.
I suggest that instead of allowing for export and import of tables an extra toggle be added to the Premium Sandbox Configuration area. When this toggle is selected NONE of the configuration tables from the Production version are copied at refresh. This would allow sites who wish to maintain their sandbox changes to do so while sites that would prefer the overlay have the option. It would also be somewhat easier to code since it is an if/else in the current refresh workflow instead of multiple new interface features.