Carter just has to be effective at doing his job.
I like him as he gets in and just does his work for long minutes, and his work is the unfashionable rock lifting and pushing.
I tend to think that's not good enough though. It seems to me like Simmons will have that role (assuming he doesn't struggle all year with injury) and we can't have both our locks just being relied on to do that. One of them needs to be more physically dominant like Dan Vickerman etc.