On my Raspberry Pi 3, the Commodore 64 games are stretched to full screen, so it looks too wide, as I'm using an 800x480 HDMI display.
I've been searching the net for answers, seems like by default (on other systems), Vice should run with black borders on a wide screen, to show the games at the proper 4:3 ratio. But not on my default install of Batocera on my Raspberry Pi 3.