Fable if You're Able

This sounds like a wonderful challenge Aesop. My question is:

Since you'll be doing the initial judging, it would be helpful to know what your stance is on a fable's moral? Does the moral need to be 'serious', such as "United we stand, divided we fall", or can it be comic or sarcastic, as in 'No good deed goes unpunished'?

Thanks
Kelly