In a large saucepan, bring the two wines, sugar and vanilla pod to the boil. Put the mint and basil in the centre of a small piece of muslin and tie with string to make a bag, then add to the pan with a few turns of freshly ground black pepper.
Remove from heat and leave to come to room temperature. Remove muslin bag, add raspberries and the melon balls. Chill for at least 4 hrs.
About 2 hrs before you intend to serve the fruits, add the strawberries and wild strawberries, if using, to the syrup. Serve in a large serving bowl or four individual bowls. Pour about 2 tbsp of the pink Champagne over just before serving.