When we weren’t sure about our cover design, we thought it came down to the overall amount of yellow in the cover. But our heads were stuck inside some box and losing sight of the forest through the trees — thinking that a tint or hue or tiny tweak to color was going to impact visibility, reader interest, or sales.
It took two posters in the Scribophile forums (I’m a member) to help us see the real issue.

This is what we thought was such a big deal — the amount of orange-yellow tint in the two cover options.
“If the choices are just those two …the yellower version is more evocative. But I would suggest taking it even further. If your story includes murder — how about doing the image in red — or parts? or making it darker to appear more sinister … something that is more evocative of the story. Just a thought.”
This was from E.M Hale and he was so right, so true!