As time passed, my existing double eyelids started to look like my eyelids had caved in, and the line behind the fold loosened, creating asymmetry, so I ended up getting revision surgery. I was very worried before surgery, but during the consultation they explained my current eye condition and the direction for improvement in detail, which helped me feel reassured and decide to go ahead.
After surgery, the area that had looked sunken has become much more natural, and the loosened line behind the fold has been reestablished well, so the overall eye shape has become much sharper and more balanced. I'm still recovering, so there's still some swelling left, but I expect it will look even more natural as time goes by.