It'll have to be a Ray Allen situation.. AKA we sign Horford to lure Durant. Without Horford we have no chance of landing Durant, at least with the pieces we have currently.
You gotta assume coming to the East has some sort of appeal, KD can instantly go from a 3-5 seed in the west to a #1 seed in the East. The only other scenario that is better for him is GSW but I don't see him being the type of player to go to the best team just to win.
In my opinion this is easily a #1 seed in the East.
Horford
Durant
Crowder
Bradley
IT