We use document numbering and revision processes to make changes to projects and will often open an existing project, check a few things, then save it as a new revision.
We have to find the existing project file name from somewhere to copy & paste it into the new Save As dialog filename field, then edit the version, doc number as required.
It will save us a lot of time and clicks if Pro would just populate the existing project filename into the Save As dialog. We can then just tweak it as required.
This is the default behaviour in many apps in Windows so please make Pro more intuitive and efficient.