I've always pictured Kelly as blonde too, mainly, I think because I see her as a counterpoint to Marian, who I see as dark. Is Marian's coloring mentioned?
I do like Westlake, too. Merigold, did you know that Orania Papazoglou is currently writing under the name Jane Haddam? It's a different series, though.
I've realized recently that though I've read Barbara's Marian Larch books and several of the opera ones, I've never read the sci-fi and an thinking I should rectify that. Are these in print?