The pot belly and serious lack of muscling concern me...I suspect given that in her "crappy yearling" shot, and this one with the belly, that she has not been on a good rotating worming program.
Conformationally, I don't like the long pasterns; they are already sinking, and that does not mean anything good long term. She may not endure heavy work very well. Nothing about her, at this point, really sticks out to me posititively. NOW, that said, with proper worming, and good food, and exercises to build up her muscle strength she may turn out pretty decently. I WOULD NOT even consider starting this filly for another year, to two years...let her grow, and mature, and become strong.