Very dark and disturbing! But what's wrong with the director?

Having seen a lot of Danish movies,I was still a bit taken aback by this dark and engrossing thriller. You almost wonder about the script writer(based on a Novel - so should it be the author?) and the depths he must have plunged to write this screenplay.

However, I am writing this because I was appalled by the Director's direction at times.

Why is the hero so angry and OTT all the time? One understands the story behind his life but still no one is so nuts all the time whatever he or she may have suffered.Just bad direction imho.
Pray tell me, why does the hero go it alone almost all the time? Did the hero make star demands that he wanted to be the one doing all the stuff? Even when he and cops discuss a move together,the rest of the team only turn up at the end to wind things down.It is repeated so often that it is almost comical and spoiled the narrative of this shocking story.

I think the story deserved more common sense all around.What a waste of an opportunity!