When it comes to the women in feudal Japan, the women for the most part, knew their place in life. Even so, I still try to avoid marrying a woman with 'deceitful' trait because whenever I do, I tend to become sick -gaining 'wounded'- or she's passing secrets to a rival clan at night when she should be instead in my bed pleasuring me. I don't have CKI yet, but that game might be representing an entirely different culture wherein a woman's crookedness might be made to seem an admirable attribute.
Also regarding the 'forgettable' characters in Sengoku...I believe in Sengoku the selfless service to the higher order (the state; the clan) was considered admirable and the point of the game. Even so, the "clan leader" is not made to be the point because even he comes second to the state and he would kill himself if it meant that doing so would serve it best.
Umm, I have to doubt that every lord in Japan was a) absolutely loyal to clan and state (what do you think plots are for) and b) forgetable. I'm pretty sure you can be selfless and loyal while still being a very colorful person.