In my current WIP, my main characters call other characters using their titles--Mr., Mrs., Miss. I can't decide whether it's better to use 'Mr.' and 'Mrs." or 'Mister' and 'Missus'. I would have said the latter, because in general I avoid abbreviations in a novel, but seeing them typed out looks dumb--Mr. and Mrs. disappear, but Mister and Missus stand out. Any thoughts?