I saw the "Follies" original twice, August and December, and both times in "Losing..." she kept her Sally hair, but Klotz put her in a plunging neckline, glittering blue form-fitting gown. I believe it's the costume she wore in NYC. (If you look it up, it's the only one shown.) I don't think it changed, but I know she didn't wear her regular costume. It was very elegant.
I liked the dress they gave Victoria Clark when the last revival moved to LA. It was more of a nod to the Collins original (but only a nod), and blue. The Peters B'way dress was still an oddity to me.