I will attempt to take a crack at in. Keep in mind I am not the coach and this is assuming Dalton and O'Neil comes back 100 percent with the same skill set. Dalton will play if she can because this is her last year. O'Neil has the medical red shirt in her back pocket and could use it instead of playing just the last portion of the year and burning a year.
Outfield= Talley LF, Bryan CF, O'Neil RF....I don't think they move Bryan. They could have Talley go to left and O'Neil to right to take advantage of O'Neil speed and Talley arm. But I think it easier to move 1 player than it is to move 2.
Catcher=Unless she is hurt Rawls will stay at catcher.
Infield= Alderick 3rd, Dalton SS, Gortarez 2B, Mayeax 1B, Milz DP. Mayeax has done a great job at SS, but I think if you put Dalton at first where she would field more throws, then you run the risk of extra pounding on the glove hand. At SS she would only field and squeeze the glove if the ball was hit to her. Just my 2 cents.