By default, an inserted chart with three values always has blue for value 1,
red for value 2 and yellow for value 3. It would be nice to be able to provide
user with redefined presets of alternative color that is easy to apply, rather
than the user having to modify each of the colors individually.
I think your bug maybe related to document theming (bug 90497).
As an update to this bug report, I brought up the topic of chart styles in
wednesday's design meeting and discussed it with Heiko and Matthias. I've asked
them to proposed data series color sets and chart element layouts, and others
are welcome to do the same.
My current research on this, as well as chart styles from competing office
suites can be found at the following link.