Sure, physically they're opposites, but in the ways that matter, I'd describe them as complimentary, not opposites.
I guess you could say that... But I wouldn't say they're complete opposites physically... Vulcans and Humans share like, 90% of common physical characteristics. Vulcans are virtually identical to us neck down (though we can't be sure about their reproductive organs, and I always imagined their female genitals to be mostly green
Height: One is tall, one is short
Hair: One is light, one is dark
Eyes: One is light, one is dark
Complexion: One is fair with a pink hue, one is kinda bronzed with a greenish hue
Yes, if we're talking DNA and basic physiology, humans and Vulcans are similar. But I'm speaking of the things that contribute to physical attraction. i don't know about you, but I haven't asked a guy for a genetic profile or an X-ray before I'd go out with him yet...