Buffy, on the other hand, had loads of technical flaws for me, yet it was still my clear-favorite of the two because I simply related more to it, being a high school-tormented vampire slayer myself (though my vampires consisted of people I had crushes on who had no idea they were vampires, and my slaying consisted of saying something incomprehensible and then literally running away ... but that's hardly the point) who sacrificed himself to save the world (that is, if you count gluing a fake-gem onto the end of a broomstick and patrolling my neighborhood until it got too dark and creepy and then running home in an undignified way though at least I didn't trip).
Serenity, for me, bridged that gap. There were what I felt to be true Buffy moments in it that I didn't feel throughout the series -- I'm shallowly including fighting-style here -- and I am newly in love as I was when Buffy aired for the first time.
The part of this post you may actually appreciate: In a rare show of true activism, I have convinced my boss to subsidize taking the whole office to a Serenity showing. Which means all I have to do is get him to do so another 2 million times and we'll have ourselves a sequel!