Real balls do nothing to the floor damage wise. So definitely let the pitchers use them. All the indoor balls do is react more realistically when they hit the floor. That is better for the fielders and catchers. Outdoor balls skip on the indoor surface, they never "bounce". Catchers will not benefit at all if their pitcher is using real balls indoors on hard surfaces except to reinforce that they need to get low and block the 5 hole. I never use real balls inside.
My daughter has never had a problem with leaping until last year. After a winter of indoor pitching, she started lifting or leaping, whichever you prefer, because of a sore toe on her drag foot. Have you had any luck in correcting it? She got called a couple times in one HS game for it, but didn't have any other problems. I still see it every time she pitches, and I was wondering if you have had any luck in correcting it.