Non-Student teams/factions

I've noticed a few ideas for non student teams and/or factions. Without clear "Guidelines" on what is allowed, I have no clue how to respond.

Ideas I've seen include, but are not limited to;

A "Band of Merry Men" inspired team. (I don't remember whether that was a student thing or not, but puttin' it here anyway)
A Pirate faction
Graduated Hunter teams
(I might have mis-remembered/dreamed this one...) A vigilante team


Anyway, clarification on what Non-Student options are could make things a lot easier.