It would be very helpful to have a renaming tool for Inventor files, with modern UI, better handling and better perfomance than Design Assistant. And there are missing options for renaming like replacing strings, new numbering and so on.
For better understanding look at the free tool "Lupas Rename" http://rename.lupasfreeware.org/ it´s old but sensational for renaming.
I know there are restrictions for renaming designs but if a power user could use it, than he could save enormous time.