It's kind of hard to explain. Some characters in Danny Phantom or Fairly Odd Parents don't have pupils, like Sam, Tucker, and Timmy Turner. I thought Applejack, Apple Bloom, and Pinkie Pie would have no pupils.
Ideas: Ditzy/ Derpy: Eye patch Big Mac: Bucket holder...thing. Trixie: Modern Magician outfit. Spike: Duh, spikey hair. Celestia/Luna: Twin with celestia being taller and more filled out. Discord: Tiger paw, Dinosaur foot, bat wings, horns.
Nice work, very faithful to both shows. Really, not only the DP style is spot on, but the humanizations are well done, very reminiscent of their ponies selves (it kinda makes the "from left to right" redundant )
I haven't seen much of this show, but I have to say you nailed Scootaloo. I wouldn't have thought it was possible to make her human while retaining her character so completely. I think you might have forgot to cut out her right elbow, though.
My other reason for commenting is to ask what Rarity's holding that's causing her to make that expression of utter loathing? I'm imagining it's the bed sheet Sweetie Belle wet.