I'm sure it's been done before. Everyone's 12 best. Would probably construct it as ABBABABABABA, similar to savage.
The other idea for a draft league is similar, except that a player can be chosen multiple times, as long as each choice is with a different franchise. So, one can pick Allen Iverson, Philly, someone else can pick Allen Iverson, Denver, someone else can pick Allen Iverson, Detroit, and someone else can pick Allen Iverson, Memphis.