Jane Wilson-Marquis   New York Magazine Pick   The Collection: Classic cuts in ultrafeminine fabrics. Softly draped silks and satins are embellished with couture details like hand-covered buttons and handmade flowers.   The Gown: Off-the-shoulder silk gown with basque waist.   The Price: $5,000.   Where to Buy: Gowns range from $1,200 to $6,000 and can be purchased at Jane Wilson-Marquis.