Tableau should have a gallery of different styled graphs for users to chose from.
There are a million different ways to make a pie chart, line graph or scatter plot map. Why aren't there different designs on tableau?
Speaking to overall company branding, many of the visualizations in the Show Me section of Tableau are too bare and plain to really "wow" a client.
When putting together dashboards, I wish there was a bank of dashboard themes or skins I could chose to apply so that graphs and charts were styled in a more elaborate or attractive way.
Consider the looks of infographics- lots of different bits of information illustrated in charts, graphs and images presenting a cohesive and stylish data visualization.
See attached images for infographics that showcase different styles, themes or skin ideas.