Stuffs like Arrow storm, meteor Shower and Lone wolves are seperate issues, especially lone wolves. Item scaling needs to be addressed and that will directly nerf Arrow storm. They have nothing to do with the armor system.
And even if you can't CC 100% of the time, what matters is that it allows you to CC before the intended turn ON MULTIPLE ENEMIES. That's the problem. MULTIPLE ENEMIES.
In the current system, you have 100% CC chance on that target, this target and 0 on the rest.
In the proposed system you have a range of 25-60% on every targets in the area after using a single AoE.
If there are a lot of AoE CC to choose from, RNG CC immediately becomes a big no. If skills like Earthquake can be spammed and on average, shut off half of the enemy team, that's just BS, not tactical. If RNG CC is to come back, skills like Earthquake, Chain Lighting and any large multi-hit skill in the game must all have their CC removed and toned down to soft-cc to make the game playable and not be a total joke.