Hypothetical scenarios such as what it's offspring may look like? Do you have information on the sire or possible sires?
Or are they looking for various possible genetic diseases?
She looks very conformationally correct and sound in the legs. To help "perfect" her I would breed her to something with a larger hind end, deeper set hocks and larger muscle, if she is being bred for stock type purposes. I would prefer something with a longer neck (although her length is adequate), but she has a relatively clean throat latch for a QH.
She's a very lovely mare, and all of that is just being nit-picky...she has a very attractive head; I believe she is nice quality for breeding purposes.