I prefer Marchesa and also thought of the designer. I do think it's a little similiar to a name like Prada or Gucci though, but if that doesn't bother you than use it!
I REALLY would caution you against using Arianne though. Like PP, it reminds me of Aryan and I would never want my child's name to have a Nazi assocation.
What about Adrienne/Adrianne?