I completely support a name change feature, and I think a Namingway item or NPC would be a perfect way to do it. I've wanted to change my character to a male for a while now, but my character's name is very feminine so it would be weird.

As for accountability, as long as a player's profile could display previous names they've had I think it would be fine. That way people aren't using it to escape a bad reputation or something unethical they've done.