+1 for scripting support.
Not only within the application, but especially outside the application.
I'm a bit flustered by the discussion on the programming language. I've done some automation of Microsoft Office. Yes, inside Office you can use VBA, but outside Office you can use almost any language.
You can use PowerShell, VBScripting, VB, C#, Python. I don't know what the technical terms are to describe that sort of implementation, but that is what I want!
My main use case would be to fill/expand a Publisher template with my specific data.
If a single language would need to be chosen, I would have a personal preference of Python over JavaScript.