Modern Linescore off-hand idea
 

Inspired by Perfect Team, I thought that to differentiate between eventful & uneventful innings, ...

0 run innings that went 1-2-3 could come back with a green zero.
0 run innings without a hit could come back with a yellow zero.

No-hit shutouts on this line score would have all green & yellow zeroes.
Perfect games would be 9 green zeroes...

Maybe on the box score/article/WPA graph page since there is already some color to the WPA graphs.

A good sign the overall game is good...