Customizing shapes in Shape Manager

Is there a way to customize the shapes used in the shape manager? Specifically, I'd like to change filled-in shapes (circles, squares, triangles, etc.) to unfilled; this is a better way to show data when lots of points are falling in the same region of a scatterplot. 

I'm running 2.9.0 on the Mac (also PC, but my question first relates to the Mac). 


Regarding lots of points: have you considered using slightly transparent colors? That might also help in overlapping visualization.