Not creative, not original. Costume drama with little substance. These type of series are puzzling. I can't think of many good films or TV-series about WW2. One that I "liked", however, was Vilsmaier's Stalingrad (1993). I say "liked" because the movie was horrible. But not because of bad writing or bad acting, but because the film shows the true horrors of war. For me, the film just left me with this idea that war really sucks big time. And I think that's a very good reason to make a movie about war and suffering.
But then there are this type of series about WW2... What's the point? I don't see what new World on Fire could give us that we haven't seen already in so many other TV-series. Are they just making money with the bloodiest war in the human history? Well, they show the history of WW2 from the Polish point of view (although poorly), that's maybe something little different. The Phoney War and the Invasion of Poland are very much worth reading about, but since this is just historically inaccurate fiction, I don't see the whole point in watching the show.
Everybody speak about how bad this war was, with tens of millions of people left dead because of it. Yet, every year new TV-series, films, video games and other stuff about the war are made and it's always with the main focus in visuals rather than substance.