The cutie mark was simplified. Ponies in G4, especially ones designed by Faust, have a strong focus on simple cutie marks. Very few have more than two colors.
Hair was changed to be somewhat unique in shape since G4 ponies have very different mane styles. I picked one that wasn’t very crazy. I changed the hair color order as well.
I considered changing her to a unicorn or a pegasus but decided against it since there was no narrative reason to do so.