Im surprised this dress doesnt have one because alot of mine like this have it, but a ribbon/cord of some kind! Think like a robe ribbon, but for a dress. You tie it right under bust and make a pretty bow and it helps give the dress a more flattering shape.

Although no shade to you, it looks amazing as is girl!

Also like someone else said, getchu some cheap necklaces from wherever you prefer to shop. Its like a cheat code. I have several lol