I have a non softball senior doing the college process now. A few things I learned:
Some hi level schools will request every sitting of sat or act. They trying to ascertain which students tested several times each semester looking for the unicorn superscore. The schools then can better assess the students average ability (on the tests).
As said elsewhere, take both tests. most schools will take either. Most students will show better results on one or the other. My DD1 did much better ACT but only took it once. Regret she did not take it earlier and prep for second sitting.
JADs DD story is instructive (it is posted here somewhere, hat tip JAD). After first test, assess which test is a better fit. DD should prep like it is the WCWS. It makes a big difference.
Lastly, schools downplay testing relative to days past (tho I personally believe it is more important than they let on). But first impressions are important and a 75+ percentile score for your target school is quick and easy for a coach to grasp.
In the larger realm, make sure she is working at the edge of her performance envelope and still doing well. Colleges want to see a student being challenged eg: a "B" in AP physics will trump an "A" in basic level.
DD1 so far has gotten positive responses on her applications. We are waiting til Apr1 for the top 3. I hope the things we learned working with her will help DD2.
Best of luck to yuor DD!