Slow PNP turn-off time, how to optimize it
Your control pulls the base of Q1 down, so you need to connect a pull-up resistor to it in order to bring it back up as quickly as possible. You will need to pick a value high enough that you don't bleed too much current through M1 when on (since every milliamp through the pull-up, R1, and M1 is wasted), but low enough so that the MPSA92 actually saturates with the voltage created by the divider created by the pull-up and R1 and M1.