Forgot to mention that I actually believe that Buffy is better than others. I mean, she was seen worthy enough to get into heaven, so that kindof hints that she is good and worthy of redemption and all that. But she's definitely not lucky - getting killed, dragged out of heaven, having to leave her previous life to take care of and feed Dawn (plus all the potentials), etc. Being lucky means winning in the lottery or getting a date with the hottest guy in the galaxy.
About her having to lead and not being besties with all the potentials. I think it was easier not to know everything about them, because it is already hard for her to send her friends into the battle and if she took the time to learn about the potentials, she maybe wouldn't be able to do what was needed - treat them as soldiers in a war. Yes, they were dragged from their previous lives and all, but it was either that or be killed by the guys-whose-names-I-can't-remember (sorry, reading about Russia and a potential new Cold War so I'm not quite in Buffy-mode). A leader has to step up and take control. Although she has messed up and the previous assault on Caleb was not the most successful one, she herself said that SHE WAS WILLING TO TALK STRATEGY AND LISTEN TO WHAT OTHER HAD TO SAY, BUT THIS WAS THE PLAN. And if they had been willing to think about it, then Andrew and Spike would have come and proven her right. You know, just saying.
And I must say that Faith and the potentials raiding an arsenal is actually the same as Buffy wanting to go to the vinyard, so who's the stupid one now?
All are welcome to point out flaws in my theories, cause as I said, busy reading about Russia and I might have missed something important (or a whole lot of important).