Very interesting, just the other day I was thinking of something like that (business card size), but using your FLING dice result matrix.
EDIT: typos
Sure. Here is the mockup for 1 face. The front would be the character bio + tracks.
The back would be the inventory + base resolution mechanic for FLING/SunHaven. Items could have a matching stat to fill in.
Then there would be the GM card with: