The 1.94m midfielder said it was a comfortable return to the All Black environment as he made three appearances during the side's northern tour.
"There's a great culture and a lot of special things go on inside that environment that you really miss," Williams said.
"Just being able to be back in there and obviously rekindle some relationships and friendships and things like that has been awesome. Not too much has changed in the All Black environment, just the professionalism has gone up another level and the greatest thing I find and enjoy about the environment is that every tour's there for you to become a better player."
Williams will play for the Chiefs in next year's Super Rugby competition as he looks to win a place in the All Blacks squad to contest next year's World Cup in England.
If he makes the trip it would mark his second appearance at a global tournament after he was part of the All Blacks side that lifted the trophy in 2011.
Williams will also likely have another professional boxing bout early next year as part of his pre-season work for the Chiefs.
Williams also said on Radio Sport today that Sam Burgess, the latest high-profile player to switch codes after making his debut for Bath in the 15-man game last week, approached him as far back as last year's Rugby League World Cup about how to cope with a potential shift.
Burgess has the ability to play a range of positions in rugby union with some coaches suggesting he would be suited to the midfield, while others believe he should pack down in the loose forwards.
The 25-year-old Burgess will also be pushing for a spot in England's World Cup side as he gets used to life in rugby union.
"I think leading in to the World Cup it'll be good for him, for his peace of mind, to nail down what role they want him to and I think it's in that backline at first," Williams said.