I'm surprised at how many PP have a negative reaction, actually! Navy fondant with lilac and calla lily accents sounds beautiful to me. But then, I just like strong color -- the uber traditional white bridal stuff bores me to tears, and my own wedding colors were forest green and navy blue.
(My cake, I grant you, just had ribbons and piping in those colors, on an un-colored bc base, but the design was pretty modern for the time.)
The only thing about this bride's order that I personally find horrifying is the idea that she *wants* cake smashed in her face. Ugh. Given that, I suppose that warning her about the potential for stains is a good idea, but...ugh!