While there are 72 residents, you won't meet them all in combat. Some are reserved to mark the admins and helpers:
~Purifier~
~Regulator~
~Guardian~

Some are to mark the players as belonging to a Faction:
Elemental
Furyan
Necromonger
Rykengoll
Merchant

All new players start as:
Freelancer

Each Faction space has it's own resident protector:
Homeland Security (Elemental)
Alpha Squad (Furyan)
Advance Guard (Necromonger)
Barbarians (Rykengoll)
Ali-Baba (Merchant)

Two are to provide safe havens for docking, no matter who you have ticked off:
Holiday Inn
Motel 6

One is to ensure that no one can dock at the destructable bases:
Phantoms

Many are provided to create a web of fun at the Roads to Glory North and South, which are also tied into the NPC Challenge Arenas East and West:
Pain Gang
Bruisers
Scimitar Legion
Korvan Knights
Usurpers
Border Rangers
Special Forces
ROX
Blasters
Rovers
Smuggler Elite
D3K

There are three protectors of the Merchant Alley:
Miners Guild
Travel Masters
ConAire

...and two main disrupters of the Merchant Alley:
Merchant Thugs
Thieves Guild

Other assorted 'good guys':
Reno Limo Service
Gantry Security
Vigilantees
Salvage Incorporated
Lucky Cab Company
Kruen Religious Police
Xel-Naga
Brunnen-G
INGEN
Chieftains
Royal Canadia Police
Kraken
Wandering Idiots
Gorgonites
Paladins
Romani
Fremen
Breen
Road Warriors
Dobies
Riders of Rohan

...and many 'bad guys'
Scavengers
The Swarm
Robot Arms
Riff-Raff
Leviathan
BioSYN
Grue
Gimps
Lunatics
Tuscan Raiders
The Lost Legion
Coalsack Vultures
Knight Riders
Banditos
Muhadeen
Kel-Morian Combine
Bohemian Avengers

Some of these are tongue-in-cheek, a product of my warped sense of humor, some are storyline, some are products of legends that became real...but all are deadly sirius. ;)

Most of the 'good guys' will have bribes to get back on their good side if you sideswipe them. Many of the 'bad guys' own bases in the Sovereign systems. If you wish to land there, you must figure out how to please them first.