It was just a quick and dirty sketch, but I realized that if I used our limited color palette to give the report tiles a bit of visual interest, we wouldn't be able to use those colors as visual cues elsewhere. Green later stood for “no variants”, a darker version of the orange indicated a variant, and blue was used for hyperlinks.
Giving the tiles a charcoal background was better, but still too dreary. And the padding was too great between the tiles.
Changing from a background color to a colored outline made the layout so much lighter. The visual language is being established here—the blue is used to indicate hypertext, and the magenta is used for titles. Further refinement includes the slight pinstriping to give the page organization, the addition of small icons to give the page added visual interest, and tightening up the padding.
The final touches that make the screen complete were making the tiles square for a cleaner look, adding a corner fold to indicate that the tiles represent documents and thus reports, and including the total gene count at the bottom of each tile to manage user expectations.