Tooltip
Prevent the tooltip or popover from being cut off at the edge of the graph.
Specific tooltip content with links.
Add unit
Add a unit on Y axis and in the tooltip.
Specific series color
You may want to specify the color of a series in the series itself, whatever its index, or for a particular point on a curve, or a particular bar on a barchart...
Size management
The chart may need to be redrawn if it is placed in a div that changes size.
Specific legend holders
You may want to position legends vertically or to separate them into different containers.
Time slider
You may want to add a timeline slider under the graph.
Theme
For the moment, ODS Charts supports 3 CSS themes : Boosted 5, Boosted 4 and a minimalist CSS theme embedded in ODS Charts.
For popover/tooltip management, it also support both renderer from Boosted 5 or 4 and renderer from Apache Echarts.