Actually, I wouldn't call her a redhead, she is officially depicted by Marvel as a brunette, but many artists do give her auburn hair depending on who is drawing/coloring her. In the cartoon, the color translated as red because they used very bright pigments in their cels, but Cyclops and Gambit also had the same shade of hair in the cartoon if you look, and they certainly aren't redheads in the comics.
This pony is awesome! I've loved looking through your work for awhile Spippo, and I was floored when I saw you did a Rogue Pony! I've been a huge fan and collector of the character for awhile and I'm also an avid MLP collector as well, so it's like looking at the melding of both my hobbies, lol.