The colors should not upstage and/or distract from the underlying information it aims to communicate. Beautiful is subjective. Instead, channel your inner journalist and aim for objective, neutral, etc.
Like most visual asthetic efforts, when in doubt (and that's most of us), "under-designing" is better than over-designing. And there's certainly no shame in borrowing a color palette from a previous effort that just worked.
If you find yourself wanting to apply creativity to your data visualizations, put down the gun (i.e., mouse) and go for a walk.
p.s. Also, don't forget to pick the right type of chart for what's to be communicated. We've all seen too many instances of "Ooooh. *That's* what's wanting to be communicated??!!"
Like most visual asthetic efforts, when in doubt (and that's most of us), "under-designing" is better than over-designing. And there's certainly no shame in borrowing a color palette from a previous effort that just worked.
If you find yourself wanting to apply creativity to your data visualizations, put down the gun (i.e., mouse) and go for a walk.
p.s. Also, don't forget to pick the right type of chart for what's to be communicated. We've all seen too many instances of "Ooooh. *That's* what's wanting to be communicated??!!"