Add support for gridlines and striplines for additional y axis.
Allow the user to drag the chart area and perform panning in this was as an alternative to dragging the scrollbar.
Expose public API for hover / highlight interactivity from code (currently hover action is triggered only if you physically move the mouse over the chart item).
Chart: Allow user styles for interactivity features.
Add DateTimeToDoubleConverter so Axis.MinValue / Axis.MaxValue can be set conveniently in XAML as DateTime strings.
Allow toggling the visibility of a series by clicking an item in the legend.