after poking around a little more online i think what i want to do is set the console/terminal resolution and colors after exiting pcsx-rearmed to how they were before launching pcsx-rearmed.
these are the framebuffer lines in my /boot/config.txt:framebuffer_width=320 framebuffer_height=240
(not sure how colors are set - i don't see any lines about that.)
but i don't think i can just add these lines to my quit.sh script mentioned in my original post, can i? because those aren't commands. (i just tried and it had no effect.)