Just remember, Exit Speeds are a useful tool, but don't get all caught up on it. I would take at girl with an Exit Velocity of 55 and a .450 avg. over an Exit Velocity of 70 and a .250 avg. any day of the week.
DD might be the smallest on the team last season, but all the coaches agree she hits the ball harder than anybody else on the team when looking at tee work and soft toss. However this did not translate to distance in the game. Why? mechanics breaking down and not squaring the ball up enough. And when the scatter time she did hit the ball very hard they were lined shots 5 feet high. So high exit speed in tee work and soft toss is great, but reproducing in a game or even front toss might be a better indicator. That's why I am enthusiastic about next season, she's currently hitting the ball a ton, to all fields and consistently in front toss so far this off season.