Judging a Book By Its Cover

Last year I released Twelve Nights of Christmas, a collection of dark stories themed to the Christmas song "Days of Christmas." Some of the stories had originally been written for the Dark Valentine website promotion for the season, some were written especially for the book. I was pleased with the collection, especially my story "Birds of a Feather," which was my version of the "turtledove" stanza.
Sales were whatever the opposite of "brisk" is. 
(And is there a direct opposite of "brisk" the way "inept" and "adept" are linked?)
I've decided to put out a version 2.0 of Twelve Nights of Christmas (now called The 12 Nights of Christmas)  this year and I'm going to change the cover. the current cover is intriguing but isn't getting it done.I've done that before--the original cover of Toxic Reality was elegant and dark, but when Indie Author Services came up with a more "in your face" image, sales picked up. (Briskly.)
One of the beauties of epublishing is that you can change things up with relative ease. I've edited and revised the copy, I think the new cover more accurately reflect the kind of stories I write.
The new version features an image by Linda Bucklin, with design stylings by (again) Indie Author Services.
I've pulled the book from Amazon's "Select Program," and as soon as the time period of that runs out (mid-September) I'll debut the new version. I'll be very interested to see how it does with the new cover. Thoughts?