IMO, O'Grady has significantly more potential than MC or SG. Hopefully she stays, even if MC does as well.
They are different players. Sharon is a traditional big in the mold of Cavey/Doolittle. O'Grady is more of a combo F/C who can stretch the floor to some extent. Still waiting for her to hit from outside 15.
Sharon has good range 15 feet and in. She has the advantage as a defensive presence and was a better shot blocker/rebounder than O'Grady is/has been so far this season.
I would really love if O'Grady is able to redshirt next season. She is a little raw yet not being a starter in HS and having limited minutes this year and could benefit from a year to work on her footwork and S&C. She is a little light and gets bullied a little, particularly on D. We are also really loaded at the 4/5 next year.
Sharon is already very strong and more physically adept to BIG play. A lot will depend on her rehab and where she is at the start of next season. But go back and look at her game VS Michigan last year where she put up 10 points and 3 rebounds in 15 minutes of play. It's easy to look at her numbers and overlook her but she did flash in limited minutes. She had some nice blocks last year too which is what I most remember and she passed well kicking to Mckenna or out to the perimeter for threes.
They're just different players. But I could see good things from either depending on how things shake out.