There's too many names that come to mind when I think of all the dead wood in the group that either didn't fit in or whose only contribution was standing around wearing an NWO shirt and saying/doing nothing of importance:
Vincent (Virgil/Vincent was literally one of the most boring wrestlers/personalities to ever grace my screen)
Wallstreet
Scott Norton
Disco Inferno (his gimmick didn't fit the rebellious nature and gang-mentality of the group)
Jeff Jarrett (see above... although no one really remembers NWO 2000 anyway)
Disciple (only got a spot in the group due to being Hogan's real-life buddy... what's funny is that they beat his ass at Hog Wild '96 when he first tried to join, but then later decided to accept him into the group anyway... OK)
Stevie Ray
Bret Hart (obviously not a bad performer on his own, but he was one of the worst additions for the simple fact that he had just garnered a bunch of sympathy months before due to the Montreal Screw Job, and now they're trying to force a heel turn down people's throats by making him the 67th member of the NWO. Never mind that his heel turn was one of the worst written and most nonsensical heel turns in wrestling history. If my mind recalls correctly, he said was that he hated Hogan, but because he hated Savage more for some reason, he was willing to join up with Hogan, his second worst enemy, just to do battle with his worst enemy. Of course, no explanation was given as to why he hated either man, and there was nothing left for us to fill in the blank ourselves since they had no on-screen hatred for one another stemming from their old WWF days together.)
IMO, Eric Bischoff, Buff Bagwell, Nick Patrick, Scott Steiner, Konnan and Imposter Sting were all great additions.