I hope you find the perfect article, and I'd like to read it too.
I don't have a little girl, but I give my five-year-old son a lot of leeway on choice of appearance. Right now, for example, he's sporting a mohawk even though I cringed initially at the idea. If I had your child, I would give up on barrettes and pony tail holders if she just can't stand them.
Our son sometimes overreacts. The times in the past that he's been unbearable/aggressive at home, I have consistently punished him. That doesn't make the problem go away forever, since kids can be strong-willed by nature, and ours is
extremely strong-willed, but it does often help in the short term since it reminds him that there's zero percentage in being bad. Still, I actually cherish his stubbornness, praise him for it when it's displayed in a good way, and would never want to "cure" him of it.
When punishing him I explain that part of my job as a parent is to teach him the right way to behave, that I still love him even though I'm punishing him, that I wish I didn't have to do it, why what he did is not the best choice, etc. But when the hammer comes down, it stays down, with no right of appeal.
