I agree that this feature would be extremely welcome to put it mildly. I just wanted to point out that you can take advantage of the image getting "stuck" to the note even if removed. When I get a note that doesn't use my preferred image (usually because I added it later), I use the following steps to "fix" it. Create a new note. Copy and paste the image that I want for the snippet into the new note. After a few moments, the snippet image loads. Then I just copy the rest of the original note and delete the old one. Sure, it's more work than simply clicking an image and selecting it but I found found it to be worth the effort to get the snippet image that I want.