If the author didn't want to perpetuate stereotypes, he had two choices: include the stereotype, but make it a source of conflict (which could include internal conflict even if Naomi decided not to bring it up with Raye explicitly-- she could at least be shown to have been bothered by it, or SOMETHING), or just not include the stereotype at all. It had no particular plot or character significance, and the work would have been essentially the same if it had been omitted altogether.
You speculate that she is "trapped" or that the relationship was unhealthy in some other way, but there's absolutely no other evidence of that. It would be one thing if this were depicted as an unhealthy relationship: in that case, even without Naomi herself actively saying, "Hey, this is wrong," the message would still get across. But the exact opposite is true: the way their relationship is portrayed, the clear implication is that expecting the woman to turn off her brain and focus solely on the home the minute she gets engaged is perfectly proper and natural. And I'm sorry, but that's just plain messed up.
It's not a matter of "changing" the characters around, it's a matter of what makes sense in the context of everything else that has been established about those characters. There is no indication that Naomi is the sort of woman who would put up with that sort of thing, and every indication that she's the sort who would not.
I can buy that the author may have intended for Raye Penbar to be kind of a sexist jerk. Lord knows it made me feel a lot better about it when
But the intention was clearly for the audience to sympathize with Naomi and want her to succeed, and given the ass-backwarRAB way her character is portrayed, that's pretty hard to do.
Misa I have less of a problem with, honestly, because she's clearly a sociopath. She's not supposed to be any kind of model of how a woman should act. We might sympathize with her, but if we do, we pity her because we know that her devotion to Light is unhealthy and will never be rewarding or fulfilling to her. And we know that Light is just using her, because Light uses EVERYONE. The relationship is shown to be unhealthy, and so even without a character explicitly stating, "Hey, this is messed up," the meaning is implicitly understood by both the author and the audience.
It would've been nice to have had a balance to that, an example of an intelligent, competent woman in a healthy relationship, and clearly Naomi was meant to be that, but just as clearly, she fails.