Thank you for taking care to answer, Paul.

At this point, if someone could confirm that an English-language version of Office 2003 can manage foreign locales off-the-shelf (setup of keyboard, etc.), this would seem as the safer bet.

Did you manage to find a download link here ?

Microsoft Office 2003 Language Pack - Free downloads and reviews - CNET Download.com

I could not.

I do have the .docx conversion utility, and it works, but there's always a slight delay each time I open a .docx file, so I've reverted to .doc, despite all the (theoretical) advantages of the new format.

The lost features post-2003 are things I saw mentioned by advanced users / expert writers shortly after the transition. So this could have been corrected down the line. It was mostly small things, but this accumulation of small things is what makes the difference between Microsoft's Office, and other similar suites.

As for the other, larger innovations introduced, I find it striking that 17 years of development by the mightiest desktop software house on the planet produced only that. That, and the ribbon, an interface "innovation" hated by so many, that it's hard to understand why Microsoft did not offer an opt-out later down the line.