@brianmcm these are really more Linux specific / raspberry pi specific questions rather than retropie. RetroPie has some modules for getting dualshock controllers running .

I've done some camera module stuff on the side but I mostly used crontab and spoofed the time on the pi to create a mobile schedule to automatically start, take pics every minute or so, and then to shut down after 8 hours of use.

As far as integrating it I'm sure there is probably some way either through something like the Linux joystick remapper or some custom code to link your Python scripts to your key presses, or technically I guess you could utilise the functions from the RetroPie setup script, you could technically add custom code that adds a menu for your functions and then it will just use the default joy2key implementation for selecting through the dialog GUI