There you have it in a nutshell, Alan. That was why Uhura was there. No question about it. Also, Shatner was not noticeably overweight at the start of that 5-year mission. He did...umm...expand a little as the series went on, particularly after it was into reruns.
There is really only one man who comes very, very close to the incredible smouldering sex appeal of William Shatner. So close does this man come that it could be said they are in a dead heat for the top prize. And that man is.... (drum roll)