Stop trying to tweak Kennen into viability. It's not happening.

Kennen is an artifact of simpler times. He was a good pick in seasons 1, 2, and part of 3, and then mobility creep happened and everything began shifting away from sustained damage, and more towards burst damage.

In the current state of the game, Kennen's kit cannot be viable. He revolves around his ultimate, but there is too much mobility in the game, his mobility is poor (i.e. expensive, allows time for reaction, completely stopped by any form of slow or CC), and he has to trade off between survivability and damage. If he rushes survivability, his ult's damage isn't high enough to significantly chunk anyone who stays in it for the full duration. If he rushes damage, he can be blown up within a second of getting in range of any high priority targets.

Outside of his ultimate, he's all around sub-par. His 1v1 is abysmal against a skilled player; the damage is so low that many top champions can eat a combo from him and just heal through it, and many other top champions can guarantee a kill on him if they touch him.

There are too many problems. Other changes are needed.