We have Williams. We don't need Noel.
To be fair, Noel is a better overall athlete than Robert Williams. He has better lateral quickness and can switch 1-5. Noel's issues boil down to work ethic and attitude. He should be one of the two or three best defensive Center in the entire league. It's still not too late for him to figure it out.
How is Noel a better overall athlete than Robert Williams?
Williams has the higher vertical, while Noel has more lateral quickness and speed. Noel can run the floor like a guard. They are both excellent athletes. I just believe that Noel has slightly more defensive potential, especially in the modern NBA.
To be fair, I haven't followed him much over the past few years. Maybe he's lost some of the agility that he displayed in college.