Buff Kennen

First off I'll list the positives - Kennen is probably the safest laner in the game. He's ranged, and being energy based means that he can Q minions at 1000 range without the fear of being zoned out. He has a gap closer making it easy to escape from ganks and has a reliable initiate (the ult) in case the enemy pushes the lane.

But now the negatives, and wow there are many. He does not have the damage, range, or reliability to be a threat. In top lane his damage is simply too unreliable to be a lane bully. Your Q is a skillshot that is blocked by minions, your W procs once every 5 autoattacks, and to use your E you have to get VERY close to an enemy. If you're mid lane and your enemy is a Xerath or Ziggs they'll poke you to death and you cannot fight back because again, your Q is a skillshot that is blocked by minions.

The main problem is that his autoattacks does not scale with AP. The entire reason why Teemo or Lulu are strong top lane bullies is because they have AP scaling autoattacks. Kennen has to build AD in order for his autoattacks to hurt (W scales from AD), but the problem is that he's an AP champion. Jayce builds AD and he's an AD champion, and this makes Jayce the much better Kennen in the top lane.

In a way he suffers from reverse pre-buff Tristana syndrome, where early game you want AD to be able to harass the enemy, but mid game when you transitioned to AP builds your damage sort of falls off until late game. And speaking of late game, Kennen doesn't have the best late game. That AoE ultimate is too RNG dependent and again, doesn't deal enough damage, and the cooldown is too long. If you did not lane against an AD champion then you will not be able to rush a Zhonyas, thus screwing over your teamfighting potential.

Only viable Kennen play I can think of is to take teleport, farm farm, and farm, and when a teamfight happens in bot lane, TP in and use your ultimate. You don't have to worry about being OOM because you don't use mana. But even so, other top lane champions can do it better.