My suggestion is to make out multiple sample lineups with your daughter in the various positions she plays to help the coach realize how valuable she is.
Or just have her politely ask what role the coach sees for her. I'm sure some coaches don't like that, but I don't think those are good coaches. A good coach should always welcome an open dialogue with players about their roles and what the expectations are as long as it's not just complaining about playing time.
To your wife maybe. NOT to the coach!!!!! Quickest way to be labeled as "That Dad."
If your DD had not been given a primary position then it's up her to go out there and beat someone out for a position. She needs to learn how to compete for a position she wants. If she doesn't beat someone out then she needs to work harder than she is.
DD needs to ask coach where he sees her helping the team the most. She should communicate that she is happy to help the team, and wants to practice specifically to help her prepare for her role on the field. Since there are different drills based on positions, this should be pretty straight forward and coach should have an answer. But it should ALWAYS come from your DD. She can relay the info to you. If coach is wishy washy or refuses to give her any idea of where she will be (note I did not say give her a position, as it may be several) then maybe you ask if you guys can chat about what he sees as her contribution to the team. Again, not "Where are you putting my kid" but "Where do you think she can best contribute to the team?" This should open a dialogue if need be. And good luck! We have two utility players that play everything except pitcher, one can catch too. It just goes to show their all around athleticism and skills. Kudos to your DD for being that kid!
You should have a good idea which position she is best at. Is she decent or better at most positions or is she just not a good fielder? In any event if she can really hit they'll find a place for her. It's nice to have players who can play several, but they have to know how to play them.