I think you have an adorable little filly here!
I just got back home from a breeding internship at a huge Arab farm in California. 120 arabs 24/7 can really give you an eye!
Her body is already developing wonderfully, I love her short back. I do agree with the others that it isn't always fair to judge a little girl like this since she's 'going through the funks' as some breeders will say. Her neck should catch up the rest of her and her butt will drop down too. Although her head isn't in the extreme show horse category(not sure what you are planning to do with her) I do like her soft dark eye and who knows, maybe her head with change with some age too. Nice shot of the awesome hock action this little girl has too! I think she'll be an cool riding horse or even broodmare.
Overall, she has lots of potential. :)
And as far as the lunging that was brought up I don't consider it a big deal, they can do a lot more 'dangerous' things just running around in the pasture.
I hope you have lots of fun with her!