Vulcans are only touch T's as far as we know, but T'Rina would fit the bill for an ambassador.
As others mentioned, Vulcans have been seen performing remote telepathy too. So, they're not strictly touch telepaths... its the 'mind meld' which usually requires touching and is a more 'intimate act' if you will.
Remote telepathy such as the one used by most telepathic species, allows communications remotely, and potentially reading other people's thoughts. However, the mind melds are different... they are more 'immersive' and probably allows a Vulcan greater context behind understanding an individual's actions and thoughts.
Remember that thoughts can be stray, interpreted in any number of ways... but mind melding merges both minds so you get intimately familiar with each other's thought processes that's not really left for interpretation.
I'd surmise that mind melding is essentially for gaining far greater insight and context into how an individual the vulcan is melding with works.