For Charachterization, I love this link
http://tvtropes.org/pmwiki/pmwiki.php/Main/CastCalculus
Im not too familiar with infinite worlds, but What you'll need could largely be filled by the Archetypes laid out in ACTION 1.
I would suggest
Wire Rat/Hacker (digs in and pulls out data)
Faceman/Investigator (Talks to people and gets data)
Shooter (Or melee Heavy)/Demolitions (Kills people and blows stuff up)
For a 3 person group.
from there you could divide the duties or add
Wheelman/Medic
Assasin/Cleaner
Doing a direct mapping from the show is different as they often display whatever skills and knowledge the writers need for that episode.
Nymdok