Having just watched the first episode in the series, I suspect this just might be a compelling miniseries. The casting is great, the locations evoke the settings' era justly and background story of industrial change sets a "peasants fear of the unknown" tone well. My main issue or complaint center around the preponderance of terribly annoying "mood music." whenever there isn't dialogue; a trend I see more and more frequently in UK period productions. I am not against music at all, but it should not be front and center in scene after scene forcing the mood; the camera and acting can and should do that with music being an accompaniment.
My second issue, and this not only pertains to this series, is the use of "natural lighting" which leaves us in dark interiors where one cannot see anything. I know this became trendy 20 + years ago with Lars Von Darkness, but I really can't stand it. I don't think we need to light like the 40s or 50s, but goodness me, shine a F*#%*ing light on the set; I know it's 19th century and it was dark. I'm giving it a 5 until the end of the series.