She looks Quarab to me (the Qh/Arab suggested before) we have one mare at the place I board at now that looks almost identical except that she has paint on her. The fact that she looks Quarab does not mean that she doesnt have some appy. There are differences with horses among the same breed for instance TB's were bred out of sporthorses and arabs so a TB can have a bigger bolder appearance of the sport horse or the refined and dish-faced look of the arab. So it could simply be that the QH in her has more of the Arabian breeding that shows. I however do not see Appaloosa in her. She has a full mane and tail, she is not so uphill as most are, and her feet don't say appy to me.
Striped hooves and vitiligo are not limited to appy's striped hooves are common with paints QH TB I even worked with a holsteiner that had it. This paint mare I was looking at buying even has it. It is faint black spots in the corner of her mouth most was on the other side but it is not part of her color.