DS9 era klingons believe in honor the same way republicans believe in family values. They talk about it a lot, they tell a lot of stories that cherish it, but only a handful of them actually practice it.
And that, to me, is fine. Alien species in Star Trek are used as symbols or concepts, just as it was back in the days of Swift with Gulliver's Travels. The irony, of course, is that by stereotyping aliens collectively to represent a concept, you also deny them the capacity to be anything other than that concept. And so Trek always wrestled with that dichotomy. Think of Day of the Dove, where the Klingon commander had to be willing to enter into a truce with the Federation to neutralize a common enemy. Think of I, Borg where Hugh broke with the collective, and later 7 of 9 of course. You could even include Trek V here. The idea of a Vulcan who decided NOT to reject emotion was a bold concept, one that was only partly explored through Spock's semi-acceptance of certain aspects of emotion or emotional attachment through friendship. Think of The Enterprise Incident where the female Romulan commander almost scolds the Federation for not being as sexually enlightened. There is an ongoing dialogue through Trek about prejudice and individualism. I think it would defeat the purpose to have every alien race have the same level of diversity as humanity, though. They have to strike a particular chord that is in some way 'other', and not confuse people by being too complex. Movies and TV are not National Geographic.