I have been very fortunate to have had feedback from knowledgeable authors on LinkedIn regards the cover art for Quick Fix. The two covers I had created were put forward to the forum and in short, nobody liked them. I have since created a few more taking the contributors suggestions into consideration.
The main points were :
Size for an e-book should be 1575 x 2550 pixels (at 300 dpi)
The title and Author name must be visible when displayed as a thumbprint
The cover should be bright and stand out
The cover should not be too busy
The graphics should give some indication of the books contents
If you would like to vote, please go to https://rihannawilding.wordpress.com/2015/05/12/new-cover-options/