My own take is that BW directs one down a specific path envisioned by the author(s). That’s fine but one can determine how to redefine certain stereotypes to fit your own conception of the setting. Taking the City Guard LP, the ‘Drunk’ 1pt character trait could be replaced by another that the GM/the group believe encapsulates the average city guard - looking at the list of traits there are any number to run with.
Wholesale changes to the setting are much harder, so I personally would not use it for anything very different from a quasi feudal setting.
Regards
Edward