Thoughts on ribbon around waist and/or tied around bouquet?

I don't think i'd do a belt with your dress either

I belt or a sash won't work with that dress.

I would not add a belt because then it would break up the line and floral patterns of your design. Plus, it may contrast that cool, geometric neckline. There are 1920s details to this dress beyond the pattern. If you look up other dresses of the time, they tend to be boxy, almost androgynous, drop waist, with a ruffle at the bottom. I would capitalize on the sleek, slinkiness of your dress which has a more modern shape. The flowy bottom area (pleats?) is longitudinal rather than horizontal, so a belt would break up that line.

It cuts off the natural lines of the dress. Remember what Coco Chanel said: Before you go out, take off the last accessory you put on. Wear some great earrings and call it.

I honestly think it would take away from the dress itself. The silhouette of the dress, the style of the dress and how the lines flow. It would be much more elegant to have around the bouquet of the flowers or wear the ribbon some kind of way in your hair (depending on how you are wearing your hair ex: updo). Your dress is beautiful as is!!!