[pvnk]

There are written rules about staff impersonation; if people want to be stupid and not follow them, they can reap the consequences.

As for the readability of certain colours, if it becomes a legitimate issue (it has been only once that I can remember), staff can take appropriate action.

Would names like @Skullmate and @oni-sensai count as staff impersonation?

No.

They wouldn't have the Staff/Admin Userbar.

It's not like anyone would want to be those people.