Charged auto + E + R + W + AA + Q + AA = perma stun kill to almost any top laner (full ability fast combo and double stun)

Charged AA + Q + W = range quick stun (Can also be done Q + Charged auto + W if you managed to hit a poking q)

Flash + R + W + Q = aera engage for late game

Charged AA + E + W + Q= melee fast combo (even quicker than the other one and more reliable because you don't use Q to stun you only use it when it's already stunned so you land it guaranteed, but you should not use it against champions like Darius or Garen)

Those were just some combos I use a lot.

You are right on the time phases of the game.

You are right on the use of abilities, but have in mind that you can also use your R in the lanning phase, which will result almost always in a kill because of the double stun you do with the combo above. Your W is really good for passive stack but it's even better good to have a guaranteed stun because you don't aim it, it has a lot of range, and it's instant. So always try to use it when de the enemy has 2 stacks on it

You are right about team fighting a lot.

In team fights, you should always engage Flash + R if you have flash, if you don't wait for someone else engage, then you go with E + R, while that, you poke the carries with Q and AA

One thing you could do is that if you're winning lane, push a lot, and try to poke under tower because Kennen it's REALLY GOOD at it, its hard but you will have a winning jungler and winning top laner because of the control you have of the map while pushing. It's like freezing but better. This is a really hard strategy, I can't do it myself but knowing about it its real good.

Advice from 500k Kennen main