I confess that you have the right of it; she stands alone in a vast electronic wasteland with nothing to reflect upon.  I kinda wondered about that.

I took your suggestion and put her in a small enclosure and made a very simple, infinite white light of zero-zero-zero orientation upon her with IDL.  The shadows will fall where they may.

I did notice that, even with IDL triggered in the render settings, I can still adjust light shadow % in the light dialogue, so I set it to .500.

I really don't know how light shadow % and IDL interact; it seems like the same function to me, making raytraced shadows less intense.

In my earlier render, I had left the point light at 1.000, which also contributed to the harsh shadows.

In any case, I set the edge to 3 and let my creaky old gear get to cranking on the render...it may take days.  After an hour or so, it was still 'precalculating', which doesn't bode well.  I am well-and-truly CPU bound.

Many thanks for the suggestions, and the free tools you offer; I shall work on the environment sphere and the IBL probes that you have conjured.

I had always, for my IBL purposes,  just rendered a high-resolution, reflective ball set large in the middle of my render scene (sans actors, of course), and used that as my IBL image...seemed to work., but who knows?