A birthday dress and my first sleeves

It was the birthdays of 2 little girls this weekend. I only managed to get one of their presents done. However R is only 1 so I don't think she'll mind it being late. For A I made a dress from one of the vintage patterns I bought.



Look, look I did sleeves. Now I know they are puffed sleeves which have a huge margin for error but I am still rather proud of them.




Now can you spot what is wrong with it? I changed the patterns form button holes to a zip for speeds sake but I don't seem to have taken enough material out of the back at the neck line. I think this is going to hang really wrong. But I'm sure I can fix it should I need to. The only other thing I'm not happy with is the fact that I used white thread for the visible stitching. I'm sure black would have been better. But having said that I quite like it round the bow. What do you think?