I thought this for quite some time. Then I had occasion to watch more Hornets ball and saw a difference that tipped the scales for me. CP3 can only perform at all on the ball, demands the ball, and is somewhat of a ball-hog and pouts when another team mate does something without his "approval". I watched one stretch where they were getting some fast breaks and for about 3 in a row the team threw the ball out ahead and didn't hit CP3 for the cutoff. They made baskets each time and I thought did the right thing, getting ahead of the defense and taking advantage of a 2 or 3 on 1 situation, but each time you could see CP3 give up on the play and stand there kinda shaking his head with his hands on his hips. Then at a timeout he obviously chewed a couple of them out. After the timeout they had a similar play available but instead of going upcourt the rebounder found CP3 to give him the ball and their 2 on 1 at the other end was stalled out while CP3 walked the ball up the court. Of course they scored and CP3 got the assist so he was happy. So from what I have seen, despite his assist numbers, he is not the greatest leader or team player. I also didn't feel like he had the same passion D Will does.
Now D Will's passion does take him out of games now and then, but he also converts it into leadership and drive for the team not just himself. In all they are pretty close as players and stats go, but with D Will's drive, ability to play multiple positions, and CP3's durability issues I am glad we took him over CP3.