We have the pitcher cover from middle of the field to the first base line, 3rd baseman is on a dead run home and has from 3rd base line to middle of the field. Catcher is also covering as well. If 3 girls can not cover the play, 4 girls wont help either, it just makes more girls in a small area and less girls to cover a base or less girls to back up the base from the outfield.
We are talking 60 foot bases, not 90 foot like baseball. This makes more sense to me and this is how we play. Good, bad, or indifferent, not sure but works well for us.
Runner on third and your are trying to stop the score then everyone charge.