I kind of like the interactions between these types of characters too, though they also differ amongst 'themselves'. Seven and Tuvok can happily spend an hour doing their duties but not talking, (did I say "happily"? ... maybe without insecurity), yet there are differences between the two. Throw The Doctor into the mix and he adds another variation.
I sort of see Seven as having her humanity taken from her and replaced by force. THEN her humanity is forced back on her so her relationship with other humans is both one of finding herself and one of guarded observation. Almost a competition between the two selves she has identified with, Borg and Human. With Tuvok he has worked alongside with and has co-existed with humans and other Federation beings. Yet the dominance of humans has placed him under their command where they both utilise his strength in logic (a quality some humans share) but also judge him for a lack of emotion. Mostly I think Tuvok feels superior but not out of ego, it's just a difference. As for The Doctor he views Humanity and Vulcans and Klingons and Borg as having the very essence he was denied by his very type of existence. The image of a human and the knowledge of a data bank, yet he most definitely exhibits ego, which should come from a 'person'. The Doctor is weirdly complex (as was his creator).
Absolutely I understand what you mean about 7-of-9's conflicted, ambivalent two halves of her personality. In the original "The Enemy Within" Spock said a very similar thing: "I also have two halves, human and alien, always at war with each other. I survive because my intellect wins out over both, forces them to live with each other, merge together." (or something like that, I'm paraphrasing the quote).