[SmG Phoenix]

but..but 5 tahm kench would be better

True because you can still balance AP and AD and tank sorta. So one guy is licking people at 2x attack speed while another is Q-ing for 50% HP and another is standing in front of those 2 absorbing damage. That's my memory of One for all TK.
I reckon One for All Kayle is probably one of the strongest because AP AD and tank+ ult would be amazing.