No CC in a skill based game would make it more skill based because then you can run around dodging with sprint and blocking. Instead of being CC'd for free skillless hits after getting hit with a CC.
Slows also have the same effect as CC, makes it much more easy to hit.
If its hard to aim, that's great long as its not impossible (more skill). Fireball can have on impact like a little bit bigger aoe than its size while flying through the air (can hit the ground by them to hit them the farther it is from the target, the less damage it deals. Instead of soft aiming which makes it less skill cause its less aiming (purpose of my reticle friend <3).
It also makes combat more engaging. =D