This thread is deteriorating quickly.....
Here is my (maybe unwarranted?) opinion. After having "been there, done that" numerous times, the best bat for your DD is the one that feels most comfortable to her when she swings it. It's all personal preference. My DD has demo'ed the same size and weight from different manufactures back to back, and would say one felt great, and another "felt like crap". She likes the balanced Demarini's, didn't like Easton's, was "eh" on the Lousville XLT, and did not like the Xeno or end loaded Demarini. But that's just her....
My point is, all of the high end bats are pretty much the same. It's all in what she swings the best and has confidence in. Don't get caught up in all the hype over the latest flavor of the day. I would say that if she likes her current Louisville, then look there first. If she's indifferent, try out all the bats that she can. Going from Brand A to Brand B isn't going to make a good hitter into a great hitter. Especially at 10U...