Here is a Thousand Sons squad that I created for Games Day a few years ago. My primary goal with this project was to see what I could do in terms of a display base.
I knew I wanted to have the marble filled with daemon faces, which would also be carried onto the base of every miniature. I was reminded of this when I started painting the floors and bases of my new Tomb Kings army. You also saw some designs similar to this painted on the 72mm mounted Chaos Knight.
This is not a very easy design to carry across large surfaces, as I discovered! To get enough variation in the faces becomes more and more trying the bigger the space you need to cover.
Here is the display base minus the minis. You can see the daemon faces a bit better with the unobstructed view.