The texture I am using is a crushed velvet 512 x 512. I definitely get your point, Chosen, about not always needing to see perfect detail, but in this case, I was losing even the suggestion of what it was.
I woke up this morning realizing I'd need to stretch the highlighting/shading over a vertically doubled texture (looks almost as good at 2/1 as at 2.5/1) rather than squishing the texture down, exactly as you mentioned. It worked beautifully. I rarely go above 512 with any of my texturing (except to combine smaller textures into one conglomerate), but in this case, 512 x 1024 was the thing that worked.
Many thanks for the extra tips and suggestions.