Huh, that's a good idea.
Can I suggest maybe that you might want to consider starting a thread in conjunction with the fanart thread of physical descriptions/references to what characters look like? it seems like lots of people here do fanart so it might benefit you guys to lump together...
I'm not sure if I should start a whole new thread for this, so I'll just post descriptions here for now. They're straight from MB1.
Kelsier - tall, hawk-faced, light blond hair, mid-thirties, nobleman's suit (colored vest, dark coat and trousers, thin cloak to keep off ash)
Dockson - shorter than Kelsier, squarish face, stocky build, black hair, short half-beard, nobleman's suit
Breeze - sharply dressed as a nobleman, hat and dueling cane, older, a pit portly, well-styled black hair
Ham - build of a soldier, sleeveless shirt, well sculpted arms, muscular but not massive, close-cropped hair
Clubs - Dull tan overcoat, pair of brown trousers, simple white shirt, face knotted and gnarled, eyes show with disapproving satisfaction
Yeden - short with curly brown hair, gray skaa clothes, worker's coat
That's what I have so far. Feel free to add and improve the list!