I'm well aware of the CHA (this is my primary research focus :). But that doesn't mean you should strive to make things computationally difficult if you don't n

I'm well aware of the CHA (this is my primary research focus :). But that doesn't mean you should strive to make things computationally difficult if you don't need to (for example, Rijndael vs Serpent for AES). After a certain point there's no need for further computational cost.