In another thread I've mentioned Ryan O'Niell as Barry Lyndon, not only was unconvincing as an 18th Century Irishman, he was a bloody aweful actor in the film (quite spoiled it for me).
Glenn Close didn't work in Dangerous Liasons either (at least as far as I'm concerned), visually she just didn't come across as an ancient regime French aristocrat.
As for future casting, there was a rumour that Sean Bean was to have been cast as Rudolf Rassendyll in a remake of "The Prisoner of Zenda", unfortunately, IIRC Rassendyll was an early Victorian English gentleman of old family, not a Sheffield "rough" which seems to be Bean's main character (whatever the role)[1], I think the citizens of Ruritania might have noticed.

Walrus

[1] Take your pick, they all look/sound the same. In that respect, he's a bit like John Wayne