The trouble with trying to be "period appropriate" is that it often involves concepts that we, as modern folks, are hardwired to consider absolutely revolting or as a villainous trait. Things like the acceptability of war and marital rape, slavery, crippling punishment, judicial torture, killing all males in a settlement and resettling the survivors (i.e. ethnic cleansing), propaganda, and brutal violence against heretics and pagans. Other things, like concepts of religiosity and honour culture seem equally strange and alien to us and just weird.
The problem if you're trying to be completely "period appropriate", the audience will lose sympathy with your viewpoint characters, so it should only be done in moderation.
There's a way to do "period appropriateness" without having your character be a complete piece of garbage, though! I don't know if you folks have ever played tabletop, but I've recently begun playing my first game of Legend of the Five Rings, and it's interesting because everything about the setting and the way characters act and behave is drenched with these values we'd consider alien today, and it makes it very easy to accept things like the hierarchical social structure involving untouchables, the importance of honour and courtesy, and the prevalence of violence and brutality.
There are limits, of course, related to not snapping the audience out of that mindset -- e.g. LotFR has female samurai (though there is some historical precedent to that) -- but it's possible to evoke sympathy in the audience and be period appropriate if you properly contextualise the setting and characters so that the audience accepts these different values.
Few stories go to the effort, of course. Shame, really.