Alright good sir.
Akuma has a demon within him, and always seems angry for no reason at all.
Souther beats kidnaps children and force them to build him a pyramid.
Does Akuma do anything that mean? No.
This obviously directly affects their ability to perform air fireballs as well. Souther, being the cooler of the two, is able to hit his opponent twice with an air fireball. Akuma, in order to hit his opponent twice, needs to shoot out TWO air fireballs.
Do I see a lack of skill there? So if Souther bothered to shoot out two air fireballs, he would hit his opponent 4 times.
Of course, Ky Kiske can hit more than both of them. But that guy as a raging homo and does not count.
Akuma is a proper gentlemen, but does he have children slaves? I think not.