I would still argue that a stacked horizontal bar with tick marks or a waterfall chart are often the better solutions. They also make it easier to provide a ref

I would still argue that a stacked horizontal bar with tick marks or a waterfall chart are often the better solutions. They also make it easier to provide a reference point for the absolute sum of all data points I think pie charts only work in those cases where it doesn’t really matter how big individual data points are, but where one only wants to give a feel for the relative weight of 2 (max 3) data points. But then: wouldn’t a simple KPI (“55%”) suffice?