It is sadly true that the primary limit placed on producing historical pieces is that the majority of producers are scared of the cost involved! It certainly has nothing to do with history lacking good stories or dramatically engaging characters.
It must be said, whilst some history done blow by blow would be a *little* dull, it does annoy me that many modern producers/writers play massively fast and loose with *actual* history in order to 'improve' the story. I think it sells, but this has always seemed to me to miss the point which is precisely that what is interesting about historical figures is that they were real people, and the decisions they therefore made weren't always coherent, sensible, likeable or decent. 'The Tudors' is a bit of a case in point with me; very lovely to look at, broadly well acted, and undeniably entertaining, but really missing the entire point of the actual history it's relating. For a start, the fact that Jonathan Rhys Myers is never allowed to age makes a total mockery of the fact that part of the fascination of Henry VIII's story is that, rather like a good Shakespearean villain, he seems to have started out beautiful, respected and virile and gradually, as he got older, degenerated into a sadistic, paranoid, syphilitic tyrant. Rhys Myers has *always* been asked to play Henry as if he was a Machiavellianly minded 30 something with a pantomime villain leer, and that has been the basic character note for four seasons. And that barely scratches the surface of its historical inaccuracy, which includes casting many of the real players at the wrong ages, conflating 'characters' so they become, in effect, imaginary people, and frequently inventing entire subplots. I suppose there is a grand old tradition of this - after all, something like 'The Three Musketeers' isn't entirely 100% accurate in its depiction of 17th century France! - but, really, 'The Tudors' is just the 16th century 'Footballers Wives', and will hardly stand to enlighten anyone about real history! For me personally, whilst it might seem ponderous by some of today's standards, I miss the commitment to accuracy that used to be shown by serials like 'The Six Wives of Henry VIII,' to use the obvious comparison.