So this is how the skirt turned out. Excuse all the photo-tweaking. The light was awful.
Unfortunately, the scholarly gentleman who snapped the pictures failed to capture the wonderful swish, the clever a-line hang, and the fitted waist with the invisible zipper, BUT I succeeded with at least 3 of my difficult criteria. It is modest, feminine, and I can wear it just about anywhere. (I don't know how it would fare in a backpack, however...)
It also falls down (ha! not literally) in the area of stylish. It goes right down to my ankles (I tell you. Modest.) There are no gathers or garish prints. But it is quite flattering. And grey. And so utterly boring, I'm bound to wear it.