What will she be registered as?
She's absolutely beautiful! While I agree it's not a good age to judge she is nice, I wouldn't give up on her bone I feel like she will likely balance out well. I think she has bettered both the parents (ok well, mom, can't see much of dad aside from furry) which is always important. Would love to see her in a few years I don't have any major concerns at this point. Time will tell.
I agree with what rambo said about the weight. I would want her thinner and while I wouldn't cut her feed (the next growth spurt will balance her out) I sure wouldn't up it. Babies are tricky, they will look skinny/fat when they aren't. There's barely a not even there hint of ribs,on no horse would I say that's thin, plus the ribs are fairly irrelevant, especially with her current build you can't put faith on those alone, she has too much coverage overall. Look up Henneke Body Condition it may help you. Also thinner is much better then fat, especially for a growing horse.