Thanks to all who responded to this thread. I, too, like the OP, started with Firefly and wondered if I should explore Mr. Whedon’s work further.
For those who care:
After hearing so many good things about it, I bought the Firefly set early this year and worked my way through it (rationing myself to an episode every week or two, since I knew when I ran out there would be no more). I didn’t fall in love with the series immediately, but it wasn’t too long before I found myself really liking it. I grew to love the characters and their world, and the way the show avoided cliches and told original stories that successfully combined humor, excitement, emotion, and moral sense.
So I decided to give Buffy a try. I found a used copy of the first season cheap enough to take a chance on, and now, after watching about 2/3 of that first season, I’ve been on the edge as to whether to go on to the next season or give up here (and, if I do go on, how many seasons to stay with it).
From what I’ve seen, it’s definitely not up to Firefly’s level—not that I expected it to be. I’m aware that it’s rumored to get better. But season 1, at least, really is a teen show, which I’m way too old for—and it’s set in that TV high school fantasyland where all teens are rich, attractive, impeccably groomed, and played by actors in their twenties. And nobody at the school seems nearly alarmed enough that once a week somebody dies violently. And forget all the demons and stuff—the fact that Alyson Hannigan doesn’t have guys drooling all over her makes it nearly impossible for me to suspend disbelief. And the episodes run a bit to a monster-of-the-week formula, with plenty of genre cliches (e.g. all rescues occur at the very last minute, just in the nick of time). On the other hand, it is kind of a fun show, the dialogue is occasionally clever, and I can see how it has potential to become better. So thanks to this thread, I might at least give Season 2 a watch.