For Noc:
Assuming Jungle, start machete + 5pot, your ms is high enough that you might not even need basic boots when you head back. Either start finishing wriggles or get a philo, depending on stuffs. Your build from that point on is really quite... open to say the least. I've never really felt constrained to build anything as noc. That said, I find Blade of the Ruined King to be amazing on him. Ult on somebody, then instantly active them and it's almost guaranteed rape/summoner's blown. Also, he's not half bad with the Spirit of the Elder Golem, though you could probably skip it and go for a Frozen Mallet if your team is doing well.
Kennen: Kennen is squishy. So you need to build somehow to compensate for that. Hourglass is a must by the middle of the game in virtually every game, an early revolver is nice, and he doesn't do half bad with either a rylais or an abyssal. Liandry's wouldn't be bad either.