Thanks for the suggestion, John.
Did you want this feature for Aggregate Report Builder reports or the Raw Data Explorer, or both? If you’re looking at the Raw Data Explorer, you could achieve this, by saving the first report and then using a “Share code” to create the next one. You can find more on Share codes at Reporting via the Aggregate Report Builder and Raw Data Explorer.
I think this would be a great feature to add, even though you can use Share codes for Raw Data Explorer reports for now 