Head coach Steve Hansen will complete his tenure after Friday's bronze medal match against Wales in Japan.
Assistant coach Ian Foster has already expressed his interest in the position, while there are sure to be other high profile candidates.
Asked what positive traits Foster could bring to the role, Williams wouldn't be drawn other than to say he knew there would be a lot of interested applicants.
But the cross-code star, who is of Samoan heritage, did reveal a suggestion for New Zealand Rugby about the next All Blacks coaching group.
"There are a lot of coaches leaving at the end of the year, and one thing that I would probably put to the NZRU, it would be good to see a Pacific Islander or Māori in the coaching system that would have a bit of influence," he said.
"Because the way the game is going, and it is today. There are a lot of island boys, a lot of Māori boys who play for the All Blacks.
"I am just thinking how we can get a lot more out of those boys. I know that there is a bit of space there for that growth."
Williams is yet to confirm his own future after the World Cup but it's widely expected Friday's match will be his last for the All Blacks.
Quizzed on Monday if he had made a decision yet, the 34-year-old said he was still finalising his situation and would confirm that "soon".