Say a user has an offensive or inappropriate username instead of you manually changing it don't you think it'd be easier to force them to change it themselves. Obviously after a certain amount of times a staff member would probably just ban them.
If an account was FNC'd by the staff team it would take them to this page:
They can't go anywhere else on the site until they confirm a new username.
I know it'd be easier to issue warnings and ban users but sometimes you can just do something simple like this and not have to be rid of the user completely.
Any comments would be appreciated, hopefully this is something to consider.