H Ryder, welcome to the board. I moved your thread as the other forum is for software techie questions, and deleted the post in the puppy name forum as you have now successfully started your own thread, congrats!
As to answer your question - since your pup is a mix, with only a little bit of GSD in him, not very likely to have his ears go up at all.
Not knowing their background, the father being unknown, their age only approximate, it would be extremely difficult to be able predict anything about how big he will be, what he will look like, or if the ears will go up.
I think all anyone can say for sure is that your pup is cute, cute, cute!!! He will be what he will be, ears up or down, big or small, GSD-ish or something else. As he gets older, some other features may become more prominent that will indicate one breed over another, or he may just always look like some kind of mix with some GSD in him. Looking at the littermates and your pup, there is quite some variation in how they look, so who knows what breeds are being mixed and expressed?
I don't think she'll be tiny at 13 lbs in the 9 - 11 week range. I'm guessing you may have a dog that will top out in the 50 - 60 lb range, but who knows? There is nothing to be concerned about really - whatever he ends up as, size-wise, muzzle-wise, ear-wise, will be what he was meant to be, and will be fine just the way he is.
I know with unknown mixes, it would be fun to have some more info about their background, but having a completely original and unique dog is also something special.