When's the big day, Tan?
How about - Dukan moist cake (DD's muffin adapted recipe is good) with flavoured yogurt/vanilla/choc or whatever flavourings, topped with sf jelly or stewed rhubarb, custard made with cornflour on top, then either 0% from frais/greek yogurt or meringue on top. Sort of cross between trifle and meringue pie.