I’d like to suggest that when a rune word drops, that they have better visibility in the game world as they are hard to see and easy to miss. Thematically the unique text color fits them nicely, but its hard to see them against the ground in most cases.
Some suggestions would include, a higher contrast color scheme for their label text color, adding a icon on their label like you have done for seasonal items, drawing an icon on the mini map like for what is done for legendarily, uniques, mythic uniques, and seasonal items.
Additionally, for the ones you do miss, maybe they can be mailed to you, though this might be problematic, as i think this would compete with the current 10 item mail cap if you miss a few to many while zooming around and have other items in the area that will also get mailed to you.
I wanted to add, that i did notice they do mail you legendary runes you miss, so thats a nice positive, but i still stand by that its hard to see runes on the ground as they currently are and some improvements like suggested would be beneficial.