A perceptive review. What I would also add is that if the writer and producer of this series meant to introduce us to so-called "everyday Germans", we may be entitled to ask how credible is it that a group of German friends should include - in the year 1941 - one among their number who happens to be Jewish?
It is not for me here to question why the writers chose to omit the first two years of the war - it is a writer's prerogative, after all, to start a story at whichever point he or she wishes - but from my own perspective (British of Polish descent), I found the one-sided portrayal of the Polish resistance unfair to the point of caricature. (There's a discussion in English on the subject at the Krakow Post website, for anyone who wants to pursue this further).
We all know that there were those Poles who were anti-Jewish for whatever reason. But the voices which are never heard are those of the great number of Poles - whether resistance fighters or just ordinary villagers - who were murdered by the Nazis for coming to the aid of their Jewish neighbours.
But I suppose any mention of them would not be very high on the list of priorities of this particular German television company.
Cheers from Michal