In refining the new histogram component (already looks good) and how it is packaged within the Firefly environment, it would be good to bear in mind the value of being able to stick 1D histograms onto the sides of a 2D x-y plot (scatterplot) or density plot, showing the projections of the two individual variables.

This requires the 2D and 1D plots to be able to share common sets of axes, and of course it requires one of the two 1D plots to be rotated a quarter turn.

This is one type of composite 2D plot with two different chart types.