I suspect that one of the principle risk areas for mid-airs (outside of
contests) is in the pattern, near an airport. *

Statistics? What data support this suspection?

There is absolutely no
way a conventional chut can save you when you are this low, no matter
how fast you can get out of the glider. *A BRS can.

Not true! Emergency parachutes open in less than 300 feet. Not as good
as a BRS of course, but having a "little red handle" can easily be the
difference in suriviving a collision at low altitude.