My suggestions:
1) Have her dressed up so she stands out!
2) Get FP+ and be there early to be one of first let in. Find best seats and where she will be visible to the CMs.
3) They ask everyone to slide towards the middle which means if you are in middle section they want you to move deeper in. If you are on side section, inside aisle, it means staying on the aisle because they slide in from the outside aisle.
4) The forward middle fills fast so you can let folks past you if you want to keep her close to aisle. Side seats you can put her on aisle and won't have to move. These seats would be less obstructed view due to angle.
5) For sides, plus to her there on aisle aside from chance at being picked she will have unobstructed view of stage because no one really in front of her due to angle.
6) Front few rows are for Handicapped and VIP but you will be able to get to about row 3 or 4.
7) Bench seating with backs.
8) NO guarantee but it seems like almost every time the child picked is sitting (facing the stage) on the right side. Because the handicapped and VIP seats load from that side the CMs seem to linger over there.
View of theater from right side far away from inside aisle, about halfway in.
Front row and a few behind that will be reserved so you can go sit the next open row behind them.
Side section aisle seats have no obstruction since you watch from slight angle.
Center section fills first and fast but you have lots of heads in front of you. This time we arrived fairly early and family with us wanted to sit center. If you choose go in front of the technical guys box.