With active 80-column display there's no way to activate hires page2. Instead of directly fiddling with 80COLSTORE it seems the cleanest way to disable the 80-column display via the official firmware entry point.
The ProDOS 8 Technical Reference Manual states in chapter 5.3.1.3 - 80-Column Text Card:
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80-column text cards -- and other Apple IIe features -- can be turned off
using the following sequence of instructions:
LDA #$15 ;Character that turns off video firmware
JSR $C300 ;Print it to the video firmware
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Depending on the actual joystick used on a real machine the timeout in question may be much longer than expected. Therefore a potential counter overflow must be taken into account.
The added overflow check made of course slowed down the timing loop so adjustments to the thresholds became necessary. Independently from that the deadzone was significantly increased as usual joysticks have quite some backlash around the center position.