A problem with putting the letters on the sides of the icosahedra (yes, that is plural for ‘icosahedron’ according to the WordPress spell checker — which by the way treats ‘WordPress’ as a typo). Where was I? Oh, yes, a problem with putting letters on the sides of the icosahedra. The 3D letters are outlined in black, and from a distance all you can see of the letters are the black outlines, and from an even greater distance all you can see of the faces are the outlines of the black letters, the color of the faces being completely crowded out.

I tried to remedy this by changing the letter color to transparent:

Then I made the letters flat and tried a different font (Calligraph421BT — did you know there was such a thing anywhere, let alone in Sketchup?). And that did look nicer:

It looks nicer still in close-up:

Oooh, this looks so pretty I could see hanging a ‘DNA Mobile’ made of atoms like this! Calligraph421BT, your existence is justified!