This may be a series of posts reflecting on aspects of cover art I've seen in my travels. I'll point out what works or doesn't work about it for me and maybe that will get you thinking when you do your cover.
Obviously I'm not going to take someone's cover and post it here but I will take the element that caught my eye and attempt to reproduce it.
That pink (and it's color sampled so it's that color) is really really eye-catching. For me it's too eye-catching. It nearly vibrates like Pop Art. But it's not that it's practically a neon color--even for Pantone--, it's that there's a heavy black outline. It's very harsh to my eye. Trust me, I don't know what color background this could work against, but the beige doesn't do it for me and that's essentially the color used in the original.
The other problem was the font which was much more involved than this, resulting in still more black. It wasn't so much that it is hard to read--it's dark, it's bold, it's blocky, it's that it's too much. It's heavy and not simple/stylish enough.
There comes a point when you can over-design. You do too much. Less is often more.
Solution. Look at your image. If the background is dark choose a color for your text that is light. If you background is blue, don't choose orange for your text. Make text in the same or related family. If I had an image of a field of hay, that would be green. I would look for the darkest or lightest green in the image and try that. I would look at the sky. Can that be sampled and used. I wouldn't choose school bus yellow even if there is a school bus in the background.
Try to stay within the confines of the image. That's your best guide for the choice of fonts and of colors.