One of my yardsticks is do I want to have a coffee or beer with them. Some of my favorite books have characters I want to be friends with . . . you know, if they were real and all. :o)
Of course I love strong characters that have vulnerable sides/facets - often hidden, tucked away to emerge only with certain people, experiences, etc., but are overall strong, alpha.
Ok, and hot. I write romance.
I love writing. I love getting to know characters as the story progresses. Like getting to know a friend, I guess.
Happy Day All!