Featured Tiles: I like to think of this set of tiles as an example of relationships:
The tile on the left is the opening statement: "This is what I am; This is the standard."
The tile on the right is a variation or response: It takes the example of the above and elaborates as if it were saying, "I accept your statement and respond. I am an elaboration of you." Or, "I see your bid and raise you one."
Also working in this design dynamic is the shape and strong black framing of both tiles, bouncing the eye back and forth toward the center. The outer curves work in the same way, leading the eye back and forth between the tile: The left tile has a larger outer margin on the far left; the right tile sweeps toward the far right border, but a similar strong outer border on the right and the strong vertical in the center of the image stops the eye at the far right.
The tree-like center designs are isolated as images, but relate to each other in motion toward the center, also bouncing the eye back and forth, yet slowing the flow by corresponding dark verticals.
How wide the center division between the two tiles is also important. If hung too widely apart, this dynamic would not work as well.
I don't think these things as I am working. These design elements are almost subconscious and are part of an artist's "eye". They either look right or they don't.
This same back and forth happens a lot in music: Theme and Variation and so it can be in clay.
These guys are fun to move around to get different impressions.