I got a couple here,
One is to have prerecorded chainsaw ambience for the minigame. 50 chainsaws obvisouly exceeds the sound channel limit and the result is a stacked chainsaw idle sound.
I say take a prerecording of a bunch of chainsaws going off then mask it over the minigame arena.
Another is to make spawn points in the air.
Its very common to just get spawnkilled the moment you spawn so figure a second or 2 in the air would at least give you a chance to move an inch.