I expect that Allegri will use so much rotation, that the starter concept will fade. And i also believe that Lemina will start and perform more than most ppl expect!
He is great at his job, which was defensive mid, not creative regista. He had some good shots on goal, and had good tackles and decent passes. His talent is not creativity, it is aggressive defending, winning possession and simple distribution. He did those jobs well. He could become a Vidal with time, he has the skills and athletic ability.
I think he interprets the role slightly differently than we are used to seeing, and he's not doing a bad job off it, but yea I want to see him a little freer, feel like he has the flair for it, though it negates his starting position because there's a lot of options for Juve moving forward.