The current sideline grandstand is the perfect width to be behind one of the goals if you rotate the field (which would be better north-south anyway).
Knock down the field house. Build a modern volleyball gym and indoor track.
Build a new sideline grandstand for soccer.
Plus, if you run the building on the other side of the field, you can have overhangs for sideline people, easy access to ground floor locker rooms and then build dual purpose athletics offices/meeting rooms that double as business suites after hours.