Enclave Remnants are at the top of my list of course. Any group which can swoop in, kill hundreds of troops, and then leave without a trace is worth of respect. Not to mention these guys are well passed their prime with only two/three sets of PA between them.
You know, I've never thought of the Enclave like that. I think I've just gained a whole new-found appreciation of them.
1. The Khans: I just love these guys. I used to hang out around the pit hoping I could get initiated.
2. White Glove Society: I like their freaky masks and their general snobbiness. They just need to be cured of the whole cannibalism thing.
3. The Kings: They're loyal.
4. Followers of the Apocalypse: They're smart, trying to make the wastes a better place, all that jazz.
5. NCR: At least they're friendlier than the Brotherhood, and more grounded in reality than the Legion.
6. The Chairmen: I'm just sort of neutral with them.
7. Enclave Remnants: I don't really have much to say about these guys either.
8. The Omertas: Trashy, trashy people. But I like sneaking around their casino and stealing stuff xD
9. Brotherhood of Steel: I've always hated the Brotherhood. At least they had the redeeming feature in F3 of clearing the ruins of super mutants, but in the Mojave they're just a**holes. They hoard technology, they're hostile to, um, everyone, and they wear power armor. I don't like power armor. But I still haven't played a run through where I blow them up.
10. The Boomers: I can't stand them either. And did you hear what they wanted to do with that plane? They wanted to blow up everything in the Mojave with it. They're insane!!!
11. Caesar's Legion: The craziest of them all. So crazy, I am at a loss for words.