It would be cool to have for the pie chart:
* varying heights for pie slice(s)
So that pie slices at the back are higher than the pie slices in the front. This allows a user to more easily visually distinguish slices apart.
Can be tricky from a perspective point of view. You don't want small slices to disappear behind higher/bigger slices.
* highlighted pie slice(s)
So that you can select 1-N slice(s) that are 'highlighted' in a way where they are moved a certain space away from the center slices more than the rest. This allows for pie chart's focusing on a certain aspect or percentage outcome.
I've attached example pictures of what I mean.
Keep up the good work, great library.