I feel like you're focusing on the wrong thing.
The %current CD reset is nice on all of those champions, but it's not enough to warrant the 3200g price on it for the ones I listed.
It has nice effects, and a few you listed might abuse it, but the loss on so many parts of it just doesn't warrant it. The AS is useless to half the champions you listed, and Akali can't use the mana regen or the mana.
Also, keep in mind, it's 20% of the remaining cooldown. So 5 autos doesn't mean you get a full reset.
And, as I had said before, it going on cooldown whenever you ult means they lose out on a lot. Teemo places a trap in his tribrush, and suddenly, whoops, it's on cooldown, because he wanted his early warning. Kog uses R to clear casters, and it's on cooldown.
Nidalee uses her R to clear camps, meaning she'll waste it a ton of the time, too.
And, finally, just because you have AD ratios doesn't mean it's worthwhile to go into an ADC-oriented item. Nidalee's AD ratios just aren't enough to justify it, and, as I said, while Akali has good AD ratios, she doesn't need mana, mana regen, or attack speed, and her cooldowns are low enough by the time she could opt into this (About as a third or fourth item, Gunblade and Lich Bane have priority) that the 20% remaining reset would just be a joke. She'd actually drive herself to run out of energy, that way.
This will open up the item to some of those you listed, but it'll still be useless to others.