I'm not asking anyone to 'think ahead' for me I'm simply saying I shouldn't be forced to write commands that really should already exist, and I don't see the logic in your suggestion that by offering a few more commands for user/group manipulation this would result in FreeBSD no longer being freely available or 'being BSD'.
Anyway, I think we've established that there is no command to remove one specific user from a specific group so editing /etc/group is the way to go.
No biggie, case closed.