The fact is there already is a lottery. That is choosing the players. Unlike in real life where everyone knows John Wall or Blake Griffon will be the top pick and is a certain star (Well almost certain - sorry Greg Oden) in BB often the top pick can be a total dud and the best player is USUALLY picked outside the top half a dozen picks. The "word on the street" instituted this season was supposed to help but it is so innaccurate as to be almost worthless, guys your scout thought were one ball turn out to be 5 balls.
I think the system should help the lower teams more than it does now and introducing a lottery obviously reduces the worst teams chances of geting the first pick. The draft is the one way those bottom teams can get better, we should keep the system the way it is and not make things even worse for them.
If anyone follows the NFL things work even better there and the draft ensures that teams that are on the bottom can move up fairly easily.