Circles would probably be dominant, but hair shadows might be enough for some. I’m thinking that no matter how you look down on the crowd, you’re looking down. If you look at the wrestler dead on and don’t see the ring floor except as a line (edge on) then you’d see the crowd cut off and dead on further away. If you have an angle shot downwards like this, you should see people in almost the flying pose with their knees sticking out on the front row or screen the knees behind the edge of the ring and have the tops of the seats showing a bit between each row to screen lower bodies and give more depth.
Two other options:
1. Balcony standing room only. Move them back, up, and behind rails, pack ’em in tight. Them looking down means we don’t need to see head tops.
2. Risers, similar to stadiums without seats. Gradually make the rows smaller as they move behind and up out of view. No seat backs.