I've had maybe 40 midairs, and 93% were while only flying a left hand pattern without loops or rolls with two or three other guys also flying the exact same pattern, so I don't think flying a simple left hand pattern is the key. Of course that was during pylon racing where stuff happens quickly.

But in normal sport flying, I depend on hearing where the other airplanes are in the air to avoid them. Helo's in front of me, hovering 3D, and electrics tend to void my system of situational awareness. People coming up and wanting to hold long detailed conversions also mess with maintaining a mental picture of the airspace. But normally it is quite easy to track three or four other airplanes while flying your own IF YOU CAN HEAR ALL OF THEM.