A heat-map let us merge the two visualizations into one, while also offering more nuanced analysis.
The solution?
I recommended we combine the two views into a single heat-map, where time of day and day of the week could be viewed simultaneously.
This made better use of visual elements than column charts. A column can only say “my value is X on a scale from 0 to 100.” But a heat-map can produce visual patterns that reveal more subtle trends, likedead zones or windows with high traffic.
But we weren't quite there yet...