David, here's the example I offered. The people are in an arc, confirmed by the curvature of the *straight* fence behind them. I won't leave this pic up real long, just until you get a look at it:
One tip if you use my advice about laying out the trig / arcs to fill your frame..... You may want to tilt the camera down slightl, so you don't get the feet at the absolute lowest limit of the film frame. If the people dominate the frame as they should, nobody will notice a slight upward bow to the horizon beyond the subjects. I'd suggest putting the subjects bellies at midpoint in the frame, height-wise.