Stephanie Evergreen shows how you can improve your visuals by removing most of the lines:
The Lines section of the Data Visualization Checklist helps us enhance reader interpretability by handling a lot of the junk, or what Edward Tufte called the “noise” in the graph. I’m referring to all of the parts of the graph that don’t actually display data or assist reader cognition. Create more readability by deleting unnecessary lines.
The default chart, on the left, has black gridlines. These stand out quite a bit because of how well black contrasts against the white chart background. But the gridlines shouldn’t be standing out so much because they are not the most important part of the graph
I like that Stephanie keeps the gridlines. I’ve seen Tufte advocate removing them altogether but there’s a lot of value in keeping them in; just don’t make them the sharpest focus color.