See, this is tricksy. I'd have to sit on my hands if you called me "kiddo."

IME, people have funny preferences/triggers around tearms of endearment. For example, I really like to use "baby," but have known people who did not like the connotations of the word and hated when I called them by it. So I tend to go with "babe," which seems less potentially offensive, until I can tell how "baby" will go over. "Angel" is another one I can think of that I've run into trouble with.