Softball Birthday Party For A 14yr Old?

Ok so this year me and my daughter decided on having a softball party for her bithday(her birthday is in January but we are just gonna tell everyone to bring something warm that u can move around in) but anyways we are planning on having it at a baseball/softball feild and like play some games then eat lunch then everybody that came would get picked up there at the field and then like a couple of her friends would stay and we are going to get a motel room so they can swim and stuff but like what else can we do and how can we make it more fun and stuff plz help!!