Good Day KDP, Here is my feedback regarding your cover creator:
You can't resize or move a single component except for images. This is problematic for numerous reasons:
Text doesn't centre correctly (vertically), making the white space above and below your title, subtitle and/or author name asymmetrical, which is just horrible.
You should be able to move components to create new and exciting designs.
Spine text often does not centre on the spine either.
Templates, whether in KDP-Print or CreateSpace, are for those who don't know how to design and create full wraparound covers. Your suggestions run counter to their purpose. If you know how to make your own cover, then do it and skip the cover creator. If you don't know how to do it, but don't like the templates provided, then learn.