Since I am doing research for my own novel's cover, I have been looking at many, many book covers to see how they are set up. I've been thinking about and analyzing what drew me to read each book. Some of these I purchased because I frequently read the author's works, i.e. Beverly Lewis. I like anything that she writes for it's subject matter. All of her works have basically the same cover, an Amish person (or two), her name in large letters and the title.
A personal acquaintance of mine, Bodie Thoene, has written several books. We lived in the same small burg where our children went to school together, and our families attended the small community church. Anyway, her cover has vignette groups of people in period dress, with her name in even bolder letters than Ms. Lewis' books. Obviously I bought this book because I know Bodie, but the vignettes are gripping as they depict place, turmoil, intrigue, love and passion.
The third book (above) is inviting as it shows a silhouette walking on a lonely night street. I bought this book, not for the cover but for the intriguing concept of the title and the summary of the story.
Two other books in my library have pictures of the setting, one a split picture of a wagon train and two women with the title between. The second, a New Orleans street scene in between the title and the author name.
While Together in One Place rightly depicts what the story is about, Under the Cajun Moon, does not. Ms. Clark's book, beginning with scenes in the city, actually takes you on a mysterious who-done-it treasure hunt romp around Louisiana. Don't get me wrong, I liked the book and have enjoyed several of her other titles but from a strictly visual (cover) perspective, I like Together in One Place's cover better.
These are just my opinions, but all part of my own research for a cover design of my own.