Firstly, kudos to you for rescuing a horse! That's awesome. The poor horse looks so badly off as far as weight (as you said at the beginning), but she looks very happy to be with you, rubbing her head on you and all. As far as conformation, its so hard to judge a horse's full potential in a state like that, but I think when she fills out, she looks like a big, tall horse. She looks balanced except for weight, I think she has potential for dressage, and jumping as well maybe. Is she maybe a thouroughbred type, or do you know?