If it's a casual wedding, this Gaultier is qt:
For a big wedding I'd like to see her in something like this, even though I don't normally like Elie Saab, I really like the elaborate beading and overall detailing of the matching dress and veil:
It'd also be cool to see her in something beautiful from the Lacroix or McQueen archives. Anything from John Galliano too. I bet she'll end going with something from Versace or Brandon Maxwell though.