Not a lot of options there. Especially since I despise slavery and will just want to kill the Legion as I see them.
The "good guys" in my opinion are the NCR. They're trying to bring back democracy and law into the wasteland. The Brotherhood of Steel are trying to collect old pre-war technology (mostly weaponry and such), and they don't think that technology belongs to anyone but themselves. The reason why they lost at Helios One, as WolfWolf said, was because they were very outnumbered. And the reason why they stayed to fight would be a bit of a spoiler, so I'll let you figure that out yourself.
Oh, and the NCR aren't weak. They're the largest faction in the game, and though some of the weaker rank and file soldiers suck big time (just like the weakest legionaries, I should add), their elite (the rangers) are far from weak. I never had any problem with them treating me in an unfair way, so I'm guessing the reason Wolf and loco doesn't like them is because they've got a bit of a problem with authority.
Either way, the big war in the game is between the NCR and Caesar's Legion. One supports democracy, one supports slavery.
So, here's my opinion on them all.
Good guys: NCR, The Followers and The Kings Evil: Caesar's Legion and Powder Gangers Neutral: Everyone else.
But really, one of the nice things about this game is that very few factions can be considered good or evil. I guess it's up to you to figure out which ones you prefer.
If you want spoilers, send me a message on my profile, I think I have a file locked up somewhere with locations to just about every unique weapon in the game. One I would draw reference to is the Gobi Sniper Rifle, a more powerful, camo version of the original sniper rifle, and you can find it in the Snipers Nest, a perch above a legion outpost far to the east near the shore. It does however require 100 lockpicking, so any sniper should work towards maxing lockpicking early on, as this was a weapon I carried throughout the entire game. The downside, as a unique weapon it would require a mod to get a silencer.
Which brings me to my next must-have tip for New Vegas. www.newvegasnexus.com Offers tons of amazing mods to New Vegas, some I feel are almost more than required, like Fellout, which removes the ugly orange hue to the game and makes nights feel like well, nights. It's actually scary running around the wastes in the dark. Then there's Weapon Mod Expansion, which offers tons of new modification to each gun in the game, and there's also the Arenovalis Weapon Retexture Project, which rextures the weapons to make them look a lot better, notably the wood grain on rifle stocks, but there's more. Those 3 mods are great additions to Fallout NV, but won't really alter the gameplay balance. www.newvegasnexus.com also offers tons of great mods that allow you to build outposts in the wastes, character created quest packs (Like Wasteland Bounties), additional weapons (I downloaded Sniper Gear to get myself a PP2000 smg, an M82a .50 cal sniper rifle, and a M107 sniper rifle), graphics texture packs (like Detailed Normals) to some lore friendly must haves, like CONELRAD radio or Secret Stash, the former offering a brand new lore friendly radio station that feels like it belongs in New Vegas, the latter expanding Radio New Vegas from about 8 tracks up to 80, all which completely fit into the 1950's Fallout theme.
All in all, despite the bugs that plagued the game on release, I couldn't stop playing the game, because it was so well put together. It's a great additional to the Fallout series and offers much in the way of expanding over what was done in Fallout 3.
