I think her conformation is actually quite good. Perhaps that was why she was a broodmare. Her neck ties in high, but this is good. Her chest is square, elbows reasonabley free (not tucked in too tight) , pastern angles normal, hip has pretty good slope to it. Her back is a bit long, but this is typical of appys.
What I see is her stance makes me think she might have some back or pelvis discomfort. There is a very slight bump just in front of the sacroilliac joint area, and the way she tuckes her hocks under a tad, a slightly "sickle hocked" appearance but to me is not the actualy shape of her leg, but rather that she has been standing for a long time trying to alleviate discomfort on the front feet. Could be that having such long toes and such low heels has put undue strain on the tendons of the forleg and the suspensory ligaments of the pastern/toe. Once her front legs feel better, she may stand more squarely.
YOu will want to work with her learning, little by little, to both reach well under and to stretch well out behind. Working on hills and over small cavaletti helps.
If she is grumpy, that also speaks of long term discomfort, possibley.
I like her and think she may make a really nice riding horse.