Community Theatre design

We are converting a flat floor community hall into raked seating auditorium for plays, drama, dance etc. The hall has a raised stage .900 high and will have a lower thrust stage or performance at floor level in front. Open hall is 17m deep by 13m wide. Our pro bono architect has designed some raked seating first three rows 200mm intervals high (all by 950deep). The next three rows are 300 high. I don't believe that gives us good sightlines so that you can see something happening to a body on the floor of the stage, and certainly on the area in front of the stage. Are there any printed guidelines for community theatre design I can present to the meetings?