M.L.
To decorate the novelty cupcakes, it works really well to put the frosting in a ziploc and then just barely snip the corner. Hold the bag high and then squirt the frosting over the base of the shape. After all bases are done, put a little extra milk in the rest of the frosting to thin it a bit and then put a little squirt of that at the tip of the cupcake. Depending on the crowd, you can also make some cupcakes chocolate, some vanilla, and some mixed. Frost accordingly. :)
I agree with some other posters that protein is a good option. How about little smokies? They're protein but also thematic.