Originally I was intending to do the entire Whedonverse as ponyfolk, but once I’d got about four of the women typed Buffy style, I just decided to go with it all the way. So.
As Twilight Sparkle, we have Willow Rosenberg (Alyson Hannigan). Because she is the extremely bookish one, the not-strictly-sociable one who still loves her friends very much, the one representing the “element of magic.” Twilight Sparkle didn’t have friends except Spike before moving from Canterlot to Ponyville, when she learned about the importance of friendship and teamwork; Willow didn’t really have a lot of friends except Xander before Buffy moved to Sunnydale, when she learned firsthand about the importance of friendship and teamwork. I will also note that Twi’s official My Little Pony wiki article states that at one point she does use a memory spell on her friends (I haven’t seen that far yet, but hey).
As Spike, we have Xander Harris (Nicholas Brendon). He may be named Spike, but he is Xander through and through; he is best friends with our resident bookish one, he is goofy and affable and flirts with a lot of people to very little success. He isn’t always the most useful in the traditional sense, but he is valuable to the team. He is a little bit of a derp.
As Applejack, whose name I just realized was written as one word and not two, we have Buffy Summers (Sarah Michelle Gellar). NO WAIT I SWEAR THIS IS RELEVANT. I mean, Apple Jack was the one I had the hardest time Buffycasting, actually, since none of the Buffy characters are all twangy and cowgirl and Buffy herself isn’t exactly the “element of honesty” all the time for valid reasons. (Though look see Buffy owns a cowboy hat go with it.) But what got me was when AJ got all stubborn and insisted on doing everything by herself, because as teamworky as the Scooby Gang could be, Buffy did do the “it’s my responsibility and mine alone” thing several times. Also, the sister thing.
As Apple Bloom, we have Dawn Summers (Michelle Trachtenberg). See, sister thing. Apple Bloom really does mean well and she has a very good heart, it seems like from the once I’ve been exposed to her. She just wants to play with the others and not be treated like a kid, and she’s very open to people even if they’re not the obvious choice. (I.e. with Zecora the zebra, and sort of like Dawn’s unlikely friendship with Spike for a while.) And yeah, sisters.
As Rarity, we have Cordelia Chase (Charisma Carpenter). Rarity is the town fashion plate; Cordelia is the town fashion plate. Rarity is a fan of the spotlight; Cordelia is a fan of the spotlight. Rarity represents “the element of generosity,” and while that is not true so much of high school Cordy, I’d say what I know of her on Angel shows that she grows into a generosity of spirit. Rarity sometimes frustrates the others; Cordelia sometimes frustrates the others. Etcetera.
As Pinkie Pie, we have Harmony Kendall (Mercedes McNab). Really, Pinkie is just innocently, ridiculously chipper; Harmony is more judgmental and occasionally mean-spirited than Pinkie, as Pinkie is really not mean ever (being the “element of laughter”) but she is also kind of ridiculous. She’s just a cute girl used to being cute and therefore happy; she’s got her selfish moments, her facepalm-inducing moments, her foolish moments. But she’s not a terrible person, just like Pinkie isn’t a terrible pony. Just… sometimes misguided. Or something.
As Rainbow Dash, we have Faith Lehane (Eliza Dushku). What this totally isn’t just because Rainbow called her friend Gilda “G” that one time, no, of course not. And Faith is hardly Rainbow in the sense of being the “element of loyalty,” at least at first; I think in her way, Faith is plenty loyal by the end, but season 3 Faith not so much. Faith is much more troubled than Rainbow, because ponies do not come from such screwed up backgrounds as people, but she is, a la Rainbow’s page on the wiki, brash, (sometimes) competitive, and (sometimes) mischievous. I’m pretty sure Rainbow is the only pony I can imagine actually making vaguely dirty jokes like Faith sometimes does; Rainbow is also the pony I see as most likely to kick your ass, which is another thing Faith does.
As Fluttershy, we have Tara Maclay (Amber Benson). Finally, another girl whose pony analogue element suits her wholly: the “element of kindness.” Tara is the absolute nicest and the sweetest; she is also (at least at first) quite shy. She’s good at taking care of people, but she can and does get fierce when it’s required of her, even if she personally doesn’t think of herself as being particularly bold and daring like the others. And she is just the gosh-darn sweetest and I adore her. So there.
As Trixie, we have Amy Madison (Elizabeth Anne Allen). Because Amy is a life ruiner and Trixie is a life ruiner. Because Amy tries to do magic but is not as good as Willow and Trixie tries to do magic, ish, but is not as good as Twilight Sparkle. Because magic semiposer reasons.
As Princess Celestia, we have Jenny Calendar (Robia la Morte). Literally just because she is an adult and because she was a teensy bit Willow’s mentor, ish, with the computer teaching and the inadvertently-being-why-Willow-started-magicks.
As Luna/Night Mare Moon, we have Glory (Clare Kramer). I believe I mentioned this before, yes.
–your fangirl heroine.