Unfortunately the answer is "no" for this version of Data Dashboard (the only things you can customize are the maximum and minimum values of the gauge and chart). But it's definitely something we're looking to include in the future!
Out of curiosity, what's your use case? Are you trying to differentiate between controls, build a custom look-and-feel, or something else?
Edit: Are you asking about Data Dashboard or Web UI Builder? The latter does give you some more customization options.