Gameplay would be rough, but it would be cool to modify an emulator to render a level preview into the Bar, with a yellow box showing the current player location, or something.
I think NES Mario was originally rendered at 240px height with 16x16 tiles, so to fit that into 60px tall display would neatly be a div by four, with 4x4 tiles. Could be barely playable as-is, and definitely usable as a "minimap"
Yep, The NES's original rendering is 256x240, naturally stretched to a 4:3 aspect ratio. Since TVs tended to be a little "off", Nintendo also recommended not putting anything important in the top+bottom 8 pixels, so all the important info should be in an area 256x224. The hardware used 8x8 tiles, 16x16 color zones in the background, and could group foreground sprites into 8*16 pairs. Games also triggered various interrupts and flag registers based on tile location+overlap, so you'd need to render at the full size, then scale down for display.
So the perfect resolution to have a 22 player coop run. 96x60 should be enough to play. I think our mobile phone in a slide projector project we did 14 years ago should proof that. Of course we also ran doom on that one. You can see the project here: https://dividuum.de/download/beamer/
