While most abilities have apparent enough graphical effects that indicate what type of damage they deal, some aren't so obvious (such as Magic Reflection), and neither are the damage conversions for weapons. The Endgame Changer is coming very soon, and with it, seemingly a bunch of changes to the user interface that was teased to us.
I think damage type icons that prefix or affix the damage numbers would be helpful to include in the Endgame Changer because it would provide the visual quality needed to help many know what type of damage they're dealing and receiving. These are the icons already in the game that could used:
(I couldn't find an icon for pure/true damage, if there is one. An icon for it would have to be created.)
Pretty short and sweet suggestion—not much to explain for this one.