Some friends and I are going to do this anyway, but how are they? Should Kennen or Akali build AD for a more balanced team? Has anyone done this and come out with some tips?

We don't play on Twisted Treeline very much btw.

Shen - Tanky Hybrid
Kennen - AP
Akali - AP with just enough to proc her AD passive

Throw in any counter items, a void staff.

don't remember which one of them it is, might be all 3, but they'll lose 1 ad because ninjas are better alone. and you never know when that 1 ad will come in handy so thats a game breaker