there should italian and russian mafia,
bloods and crips only red and blue though not 4+ types like in SA, the yardie gang they were so funny,
you buy weapons off sum yardie guy instead of ammunation (via phone) wen u 1st begin,
female gang
hitmen (black gloves, b-claver etc) hired to take people out
pub/bar gang, if u go in their bar for a drink they start causing fights (like riot mission in VC), like only no guns, smashing bottles on heads, stamping on heads etc
just a few ideas