As this is an 18th-Century set costume drama, the costumes inevitably dominate. And I don't really think I need to say much more about them. They're adequately displayed in the trailers and other marketing material. Underneath all the costumes are two things: 1) a drama based around the law and its issue with the 'Zong' and 2) some sappy romance.
The film tries to weave the two together, but they are clearly two separate entities (do you know what else can be seen as two separate entities? An owner and their business, apparently, in the eyes of accountants). I'm not sure how accurate either part is (though I do know that the film definitely glosses over some stuff), but enough seems to fit. Perhaps if I was more knowledgeable on the subject to begin with it might have annoyed me had I spotted certain inaccuracies (I'd assume in a similar way to how 'Elizabeth: The Golden Age' irritated me).
Of the two parts, I was more interested in the parts dealing with the 'Zong' and the look at society at the time. I didn't find it to be the most expansive look at the subject (the film, as a whole, was fairly basic), but it was the more intriguing. The part concerning the romance and such (which makes up most of the marketing), however, had nothing to appeal to me. At times, it was perhaps even laughable at how it was all handled (even if the actors do what they can).
The film provided mild interest for me. There were things I like about it but the overall effect it had on me was one of indifference.