Hello & UsernameEdit
Hello Suki-san. Regarding your Username, you can actually change it. You just have to submit a name change request to the Wiki Admins. You can only change it once though. If you're request is granted, you won't be able to access your account for 24 hours at most because they will be transferring all your files, edits etc to your new username. Another option is creating another account using your new preferred username and just link the two accounts. Check out Help for more info in making the request. Ganbatte!!
You're right. You're username's really easy to remember and it does make a person have a peek on your personality. :D
My username doesn't show anything about me at all. I just used the combination of my real name and nickname in real life. It's mainly because of the credits. When I'm doing editing, I want someone I know to be able to immediately tell it was me who edited the article. I don't like it if they can't tell it was me because of the different username. But, if you take a look at my profile it does show a lot about me especially my facebook profile. Also, my signature here includes my name in japanese (romaji) though I changed it a bit because I didn't like how it sounded when said. LOL.
Anyway, let's have fun adding more info here in the UtaPri Wiki. :D