Thank you for the replies! I think she is a little pigeon breasted and unless asked to square up, she tends tends to stand under herself a bit in the front. It seems she is growing out of this a bit though as she seemed worse when we first got her. Does that make sense?
Now that you mention it, I see the post-leggedness in the back. I couldn't pinpoint what it was about her back legs and thought she had a weak and under-muscled hind end. Again, as she starts working more in earnest, it will be interesting to see how some muscling shapes her. I know it won't correct the fault, but it may minimize it a bit? Also, Maura, good to know about keeping her fit.
I don't have any pictures of her moving, but I do have some video somewhere. I'll post when I find it. For the most part, she moves like a horse rather than a pony. She seems to have nice suspension and leg action, especially when she gets going. She also seems to round herself quite naturally. There are times however, when she is being silly, that you can see the pony movement as well, but not very often.
She is a project pony that we are hoping will turn out to be a nice little evener for a smaller woman (like me) or child. Right now, she stands right around 13'3", but still has some growing to do. According to the string test (if it is at all accurate), she should mature around 14' to 14'1". She is out of a 16'1" mare and a Welsh stud.