Draymond Green should be in the conversation too. His PPG may not be there (but 7th in assist and from a big man too) with the others but for all he does for the W's I think he is right there granted I am a little bias :)
Id probably lean to Kawhi if push came to shove.......
You make a great case for the worst I'd have to look into that a little more to have an opinion, but good food for thought.