While it is great that you can easily copy instances around, it is also quite error prone.
We have 30+ SSLs, all having a dev, test and prod instance. When promoting an instance in the TX Portal, it is too easy to make a mistake and copy Dev SSL A to Test SSL B.
It would be nice if you can somehow link instances over environments, so that the default copy instance action is transferring Dev SSL A to Test SSL A.
I want to emphasize that the current possibility to copy instances freely around is still a powerful feature (eg. when you need to copy prod back to dev), but a default source-target setting should prevent users from making mistakes.