IMHO all great managers have a hard, even arrogant edge, about them. I can't think of a single "great manager" that was a lovely cuddly pudding. Personally I dislike Ferguson and his personality but I can see what a terrific manager he is ( in previous seasons I would have included Wenger in this but am rather enjoying his fall from grace!)
I think NP has that edge that could make him a great manager. I don't think this makes him arrogant or ignorant. I actually rather enjoy his crossing swords and regularly slashing Burnsey to pieces.