What comes across in NV/P2 as well as STC is that some of the actors are comfortable in their roles, and some aren't.
Some will improve, and others won't.
I don't remember who it was, but NV/P2 at one time had a young man playing Chekov who was very good. I think he's moved on now, but I enjoyed his performance.
Do you mean Andy Bray? He was good.