Only thing that immediately catches my eye is, ironically, the eyes.
The right [her left] iris and pupil are smaller than the other. While forced perspective may make something further/closer smaller/larger in size, character eyes are too close together for that to have a large noticeable effect.
My thought to improve it would be to just increase the size of that iris and pupil. To about the same size as the one on the left [her right] Or slightly smaller. And by slightly, I mean like barely a line’s width. Super subtle~
Help fund the $15 daily operational cost of Derpibooru - support us financially!