We can kind of lump together the other Quarter Quell tributes because that's what the book does. If they're not with Katniss, they're against her.
Sure, some of them, like Cecelia (District 8) and Seeder (District 11), seem relatively harmless. But they get knocked out the first day in the arena. They don't seem to want to be there, or to kill anybody. It's like their hearts aren't in it. Other tributes get killed off so quickly we don't even know who they are. It's the rare tribute, like the morphling addict, who stands out from the rest and steps in to aid Peeta and his friends.
The rest of the tributes are trouble. Gloss and Cashmere from District 1, and Brutus and Enobaria from District 2, are all mean and vicious. They're not part of the secret plans Plutarch was putting together; they are just fighting to save themselves and maybe win some fans. By the explosive end of the Quarter Quell, it seems like Enobaria is the only one of the tributes not allied with Katniss who made it out alive.