Feature that allows us to only change a card picture, without creating a whole theme?

Hi! I wish there were an option to keep a feature on “default” when making your own theme. I hate how I have to fully reset my entire canvas page just to add a picture to my cards. It forces me to choose a color for “links.” I chose black to try to keep Canavs how it was originally, although I have one course where the instructor used a dark navy background and made her links in white. Therefore, my theme cannot work for the class, making the extension unusable. I like how with Better Canvas, I had the option to only change my card pictures. Now, I have to create an entire theme, which I don’t want to do, and it doesn’t even work for my courses anyway. That being said, can we please have an option to only change card pictures, without creating a whole theme?!