Okay @aButterfly ..... Here are the traditional "butterfly cakes".  Are you familiar with them ?  

For anyone who's not, you cut our a circle in the top of a cupcake, fill the space with icing or cream, or cream cheese mixed with icing sugar (there might be a vegan version of this @aButterfly, as I am guessing you will be making vegan cakes), then cut the remaining circle in half and prop the pieces on top of the filling to resemble butterfly wings.

Here are a few other ideas ....

Just coloured icing with some supermarket icing shapes scattered on top is creative.  That's what we used to do with our youth group .... bring cakes, icing, and decorating things, and let the kids go to town with it all.