The Brewster Rockit: Space Guy! comic strip from last Sunday makes an important point about designing charts and graphs: don’t get carried away.
The goal of using a chart or graph is to distill the information behind it into an easy-to-read format for making a quick point. A reader’s eye is drawn to a chart or graph and it should be easy to figure out the point the graphic is making.
If the graph or chart is too complicated, it loses its potency. If it looks great or clever but cannot help the reader interpret the data correctly, it is not very useful. If the researcher spends a lot of time tweaking the graphic to really make it eye-popping, it may not be worth it compared to simply getting the point across.
In sum: graphs and charts can be fun. They can break up long text and data tables. They can focus attention on an important data point or relationship. At the same time, they can get too complicated and become a time suck both for the producer of the graphic and those trying to figure them out.