When I want a healthy dessert, I add grated dark (70%) chocolate to natural yoghurt. If I want some sweetness, I add dried cranberries. The cranberries definitely have a much stronger flavour, but even without them, the chocolate flavour does not come through very much. I think this is because it is designed to melt in your mouth before being eaten and the flavour only comes through when it melts. If it's in yoghurt, it's much too cold to melt.
Is there an additive or some alternative chocolate form (perhaps cocoa powder + something?) which could give a stronger chocolate flavour to yogurt which will be eaten cold?