Maybe he was a too over-the-top at moments but if you watch it again, look at it from the perspective that his character is over-compensating-- he's not as hard as he seems to be. Instead he's bitter and hurt that his real family-- the royal family of Wakanda--turned his back on him and left him to claw his way out of the gutter.
Thought he nailed the ancestral plane scene, also the sunset scene, which is probably the best moment in the movie.