I actually have been thinking about this for a while. I only got 2 characters, but I think I can come up with an effective third if I got time.
For the record, this takes place in a Caribbean setting, with Vice City and Nassau being the two major cities. Many islands from the Bahamas are featured, and Vice City extends down, island hopping all the way to Key West. A large ocean separates Vice City from Nassau and is dotted with the Bahamas islands.
This character is a 23 year old American from Vice City who politically identifies himself as an Anarcho-Syndicalist, hence many of his missions are to do with Anarchism and blowing sh*t up. He works with the Anarchist Group MAU (Movimiento armado de la Unión - Armed Union Movement). Being a pyromaniac and gun enthusiast, he creates weapons and explosives which he uses in his revolutionary activities. He also sells these weapons to the AAC, represented by THE ARMS TRADER, and that's how they come to know each other. He begins working with THE ARMS TRADER when pirates in the Bahamas overthrow the arms trade, demolishing the established enterprise. He comes to know THE HAITIAN when the Haitian Gangs in Nassau expand their business to the Caribbean drug trade, and begins working with him in order to mount the rebuilding of the AAC and hence rebuild the MAU'S internal economy and keep the revolution going.
The MAU is commonly referred to by characters as the MOUSE.
THE ARMS TRADER
This character is a 26 year old Nigerian who, along with the rest of the AAC (African Arms Corp) controls the majority of the arms trade in the Caribbean. He is generally enthusiastic of the weapons that are exclusively built in Vice City by the MAU (or more specifically by THE ANARCHIST). He ends up selling these weapons in Nassau to THE HAITIAN. When pirates overthrow the AAC, he teams up with THE ANARCHIST out of mutual need to keep the AAC and MOUSE running. THE HAITIAN contacts him with a business proposal to merge the drug trade and arms trade and make a more profitable business, which ends up having them work together with THE ANARCHIST.
This character is a 24 year old Haitian (obviously) who is a running veterans in the ranks of the one of the largest Haitian gangs in the Bahamas. Based in Nassau, he buys weapons from THE ARMS TRADER and the AAC, which he then uses to give his gang an extra edge in the fight for control of Nassau. After THE ANARCHIST is stranded in Nassau, he is helped by him in establishing the Haitian drug trade which THE ANARCHIST and THE ARMS TRADER use to declare war on the Bahamas Pirates.
So those are my 3 characters. I might actually make a whole concept topic about it - make a map and everything.