in answer to your questions..
'-why are they useful?' clans are useful because people will think you are somebody even though they have never seen you before. you get more people who want to play you.
'-what do you like about them?' not much.
'-what do they give you?' extra characters in your name. duh, what do you think they give you.
'-in what would you like to be(or in what are you)?' I would like to be in mv clan and I am in mv clan, I like mv I'm real pleased with it.
'-Do you like being clanless?' yes, I like to be clanless, to be clanless is good, but to be in the right clan is good too.