I like hhow you colored her hair However, one of her boobs looks both smaller and a bit lower than the other one and I think her waist is bending a bit awkward for that position. Perhaps you can practise by trying to find pictures or photos of people sitting like that? Looking at photographs of people is a good way to study the positions easier.
Like i said early all i can saw is that this is absolutely amazing. You have managed to create a perfect Miku with all the right colour combinations and anatomy. The colour of her hair and clothing are intense and facial expression is stunning.