Reflavouring is always an easy and safe method. Someone else have already done the balancing. And if you don't faind exaclty what you are looking for you have examples to work off.
That being said... For example getting into the baron's mansion undetected through the third story balcony is the same conflict regardless if you are flying or climbing the walls like a gecko. You have position and effect for balancing. Flying may be Desperate (easy to spot/shoot down) and Great for example.