Chakotay & Seven are like Demi Moore & Ashton Kutcher.
You know they're together but you're not exactly sure why.
Meh, Demi fell for Ashton because he's young and gorgeous, and Ashton fell for Demi probably because she was his pubertal fantasy.
But why would Seven fall for a guy with a probable secret crush on his captan, who likely had a latent girlcrush on her?
As a Borg, Seven was made to respect a chain of authority.
Chakotay is First Officer, thus the Alpha Male on Voyager.
His rank to Seven would give him appeal.
Mach 5, Ashton is young and gorgeous? I was thinking more like doofy & talentless. Demi has the money, being an actress/producer. He just riding her coat tails. Can you say: Male J-Lo?
Alpha male behavior doesn’t explain the sum total of human male conduct. We are complicated beasts, and the dark cave of our mind still harkens back to the primeval.
Much of our behavior is rooted at a level of development that’s below the cognitive and is motivated by inherent drives that come from a nonlinguistic, ancient part of our brain. Our conscious minds try to come up with convincing reasons for us to explain our behavior to ourselves, and think that they are dealing with facts while, in reality, they are being led a merry chase. We may have abandoned chimpanzee ways, but most men must admit that the blatant sexuality of a Seven of Nine does incite a degree of visceral lust.
Chakotay would most likely not ‘choose’ Janeway if Seven were available unless he unconsciously thought that was the best he could do--our self-perception very much influences who we deem a potential lover and our minds convincingly tell us that we chose this person for good reasons (e.g., she's a better conversationalist).
Who Seven would choose is not as easy. As Freud said--"The great question that has never been answered, and which I have not yet been able to answer, despite my thirty years of research into the feminine soul, is 'What does a woman want?'"
-From Sigmund Freud: Life and Work by Ernest Jones, 1953