How important is polarity in marriage?

I've read similar in a book that I also won't post on this site. The book doesn't have a sexual focus, and it makes the suggestion that a high level of gender contrast both in and out of the bedroom contributes to a higher level of attraction. Maybe based on the idea that opposites attract. Personally, I find this to be true. I'm not into the whole macho man act, but when my husband does things that I perceive to be 'manly' or that I associate with masculinity, it's attractive to me. As far as I can tell, the same is true for him when I act in a way that he perceives to be particularly 'feminine'.
Thinking of the married couples I know, those where the man has what I would deem 'feminine' characteristics do seem to be married to women with more 'masculine' characteristics. But sometimes I think each person has developed those characteristics in response to the other person - if person X is very controlling, then person Y might become more passive in response to that and, in turn, person X becomes even more controlling. The idea of 'energies' makes it sound (IMO) like a particular characteristic or energy is somehow innate to a person, but I think it's often more about the behaviours that we cultivate, either consciously or unconsciously.
That said, the concepts of masculinity and femininity are so culturally and personally subjective that they're almost meaningless.

That's a weird distinction to make. What is "masculine" and what is "feminine" anyway? In regards to sex, it isn't interchangeable at all.

I can imagine complementary traits like disciplined/caring, organized/creative, logical/emotional, dominant/passive working well for a couple. But I can't really think of anything that can be categorized by gender. Unless you think those traits are.

My husband is much more the disciplinarian (and I the comforter) when it comes to interacting with our children. However, when he does take the role of comforter, he does it with such grace and sincerity that it puts me to shame. It is an endearing aspect to see in him.