How to find the right cover?

When we have been taking pictures for the book we have not really thought about the cover. Now that is a problem. I did have a certain vision at first but that has now changed. And depending on the under title that is not yet quite decided yet, the picture on the front should be different in my opinion. The two titles I'm working with at the moment is:

Cava - Sparkling bliss Cava - The magic of nature

The first title acquires (in my opinion some bubbles, bottles or glasses of some kind. While the second would work best with some kind of nice landscape.

These are the pictures I like in some way.

PLEASE PLEASE post your opinions!