A cake can be a good symbol of peace. It is also novel, and it has a bit of fun in it - "piece of cake". The image of it can trigger only happy memories for everybody. Children don't like war, they like cake. It is also sweet, colorfull and it is always divided equally, and you always have to blow the "fire" off from the candles. The divided cake looks like a "pie-chart" which is data visualisation, and also brings the "social" element.
In the name of peace