I also don't acknowledge TFF, but if one does take it into account, I thing yakueb made a very good analysis of it.
However, I disagree about Sarek being more on the "outside" of his people. If he was placed in a position of being an ambassador to earth, he represented his people to the humans. He was trusted enough by his own people that they were willing to put him on another planet in a position where aliens looked at him and said, "That's a Vulcan". Many people may never meet another Vulcan besides the ambassador, so his people trusted him with their reputation as a planet.
However, I disagree about Sarek being more on the "outside" of his people. If he was placed in a position of being an ambassador to earth, he represented his people to the humans. He was trusted enough by his own people that they were willing to put him on another planet in a position where aliens looked at him and said, "That's a Vulcan". Many people may never meet another Vulcan besides the ambassador, so his people trusted him with their reputation as a planet.