My general advice for content modeling is to structure things as much you can without annoying your editors. More structure means more re-usability because presentation templates have more control over what to put where. A good example is names of people. If you have one field for name, you can show the name in alternative ways (such as "Joe Smith" and "Smith, Joe") and you can't do things like sort by last name. It's better to put this information into two fields.
So, you ask, what do you do when a person has one name as in Pink, Madonna, or Unknown? If you have a person with one name, use the last name field. Otherwise, when you sort by last name and then first name, all the one-namers come to the top. This actually came up on two different projects in the last 6 months so I figured I would pass it on.