I'd like to provide individual users the capability to change colors of their dashboard.
Individual A = Blue dashboard
Individual B = red dashboard
but it is the same dashboard
Unfortunately, not within Splunk core, that I know of. That said you could write some javascript which could detect the logged user/ role and update the css to the appropriate color scheme.
The easiest is to hard-code the colors on 2 different versions of the same dashboard and have one user go to version-blue and the other go to version-red.