Using supertag icons obscures whether node is reference and whether or not it has anything in the hierarchy
Explain the problem as you see it
Unlike when the node icon is just a bullet, if you use supertag icons you no longer have any visual indication that the node is an original node (regular bullet) just a reference node (dotted lines around bullet). It is also not possible to see if it has any nodes under it in the hierarchy (gray background vs no background.

Why is this a problem for you?
It makes using supertag icons problematic as you lose useful visual information about your nodes
Suggest a solution
Please somehow maintain similar visual indication while using supertag icons
